114 research outputs found
Cyclosporin A-binding protein (cyclophilin) of Neurospora crassa
Cyclophilin (cyclosporin A-binding protein) has a dual localization in the mitochondria and in the cytosol of Neurospora crassa. The two forms are encoded by a single gene which is transcribed into mRNAs having different lengths and 5' termini (approximately 1 and 0.8 kilobases). The shorter mRNA specifies the cytosolic protein consisting of 179 amino acids. The longer mRNA is translated into a precursor polypeptide with an amino-terminal extension of 44 amino acids which is cleaved in two steps upon entry into the mitochondrial matrix. Neurospora cyclophilin shows about 60% sequence homology to human and bovine cyclophilins
Nanoparticle detection in an open-access silicon microcavity
We report on the detection of free nanoparticles in a micromachined,
open-access Fabry-P\'erot microcavity. With a mirror separation of m,
a radius of curvature of mm, and a beam waist of m, the mode
volume of our symmetric infrared cavity is smaller than pL. The small
beam waist, together with a finesse exceeding 34,000, enables the detection of
nano-scale dielectric particles in high vacuum. This device allows monitoring
of the motion of individual nm radius silica nanospheres in real time.
We observe strong coupling between the particles and the cavity field, a
precondition for optomechanical control. We discuss the prospects for optical
cooling and detection of dielectric particles smaller than nm in radius
and amu in mass.Comment: 4 pages, 3 figure
On the solar origin of the signal at 220.7microHz: A possible component of a g mode?
Gravity modes in the Sun have been the object of a long and difficult search
in recent decades. Thanks to the data accumulated with the last generation of
instruments (BiSON, GONG and three helioseismic instruments aboard SoHO),
scientists have been able to find signatures of their presence. However, the
individual detection of such modes remains evasive. In this article, we study
the signal at 220.7 microHz which is a peak that is present in most of the
helioseismic data of the last 10 years. This signal has already been identified
as being one component of a g-mode candidate detected in the GOLF Doppler
velocity signal. The nature of this peak is studied in particular using the
VIRGO/SPM instrument aboard SoHO. First we analyse all the available
instrumental data of VIRGO and SoHO (housekeeping) to reject any possible
instrumental origin. No relation was found, implying that the signal has a
solar origin. Using Monte Carlo simulations, we find, with more than 99%
confidence level, that the signal found in VIRGO/SPM is very unlikely to be due
to pure noise.Comment: Accepted for publication in ApJSS. 19 pages, 9 figure
Medication knowledge of patients hospitalized for heart failure at admission and after discharge
Background: A substantial aspect of health literacy is the knowledge of
prescribed medication. In chronic heart failure, incomplete intake of
prescribed drugs (medication non-adherence) is inversely associated with
clinical prognosis. Therefore, we assessed medication knowledge in a cohort of
patients with decompensated heart failure at hospital admission and after
discharge in a prospective, cross-sectional study. Methods: One hundred and
eleven patients presenting at the emergency department with acute
decompensated heart failure were included (mean age 78.4±9.2, 59% men) in the
study. Patients’ medication knowledge was assessed during individual
interviews at baseline, course of hospitalization, and 3 months after
discharge. Individual responses were compared with the medical records of the
referring general practitioner. Results: Median N-terminal prohormone of brain
natriuretic peptide plasma concentration in the overall population at baseline
was 4,208 pg/mL (2,023–7,101 pg/mL [interquartile range]), 20 patients died
between the second and third interview. The number of prescribed drugs
increased from 8±3 at baseline to 9±3 after 3 months. The majority of patients
did not know the correct number of their drugs. Medication knowledge decreased
continuously from baseline to the third interview. At baseline, 37% (n=41) of
patients stated the correct number of drugs to be taken, whereas only 18%
(n=16) knew the correct number 3 months after discharge (P=0.008). Knowledge
was inversely related to N-terminal prohormone of brain natriuretic peptide
levels. Conclusion: Medication knowledge of patients with acute decompensated
heart failure is poor. Despite care in a university hospital, patients’
individual medication knowledge decreased after discharge. The study reveals
an urgent need for better strategies to improve and promote the knowledge of
prescribed medication in these very high-risk patients
Reconstructing the solar integrated radial velocity using MDI/SOHO
Searches for exoplanets with radial velocity techniques are increasingly
sensitive to stellar activity. It is therefore crucial to characterize how this
activity influences radial velocity measurements in their study of the
detectability of planets in these conditions. In a previous work we simulated
the impact of spots and plages on the radial velocity of the Sun. Our objective
is to compare this simulation with the observed radial velocity of the Sun for
the same period. We use Dopplergrams and magnetograms obtained by MDI/SOHO over
one solar cycle to reconstruct the solar integrated radial velocity in the Ni
line 6768 \AA. We also characterize the relation between the velocity and the
local magnetic field to interpret our results. We obtain a stronger redshift in
places where the local magnetic field is larger (and as a consequence for
larger magnetic structures): hence we find a higher attenuation of the
convective blueshift in plages than in the network. Our results are compatible
with an attenuation of this blueshift by about 50% when averaged over plages
and network. We obtain an integrated radial velocity with an amplitude over the
solar cycle of about 8 m/s, with small-scale variations similar to the results
of the simulation, once they are scaled to the Ni line. The observed solar
integrated radial velocity agrees with the result of the simulation made in our
previous work within 30%, which validates this simulation. The observed
amplitude confirms that the impact of the convective blueshift attenuation in
magnetic regions will be critical to detect Earth-mass planets in the habitable
zone around solar-like stars.Comment: 17 pages, 11 figures, accepted in Astronomy and Astrophysic
Sacubitril/valsartan in heart failure : efficacy and safety in and outside clinical trials
Heart failure (HF) treatment has changed substantially over the last 30 years, leading to significant reductions in mortality and
hospital admissions in patients with HF with reduced ejection fraction (HFrEF). Currently, the optimization of
guideline-directed chronic HF therapy remains the mainstay to further improve quality of life, mortality, and HF hospitalizations for patients with HFrEF. The angiotensin receptor-neprilysin inhibitor sacubitril/valsartan (S/V) has an important role
in the treatment of patients with HFrEF. The PARADIGM-HF (Prospective Comparison of ARNI with ACEI to Determine Impact
on Global Mortality and Morbidity in Heart Failure) randomized controlled trial has established solid evidence for the treatment of HFrEF in various subgroups. Apart from HFrEF, several studies have been conducted using S/V in various indications:
patients hospitalized with acute decompensated HF, HF with preserved ejection fraction, acute myocardial infarction with reduced ejection fraction, uncontrolled and resistant hypertension, and chronic kidney disease. Data from the German Institute
for Drug Use Evaluation reveal that implementation of S/V has increased steadily over time and, by the end of 2021, an estimated 266 000 patients were treated with S/V in Germany. The estimated cumulative real-world patient exposure is >5.5 million patient-treatment years worldwide. The number of patients treated with S/V largely exceeds the number of patients
treated in clinical trials, and the current indication for S/V is larger than the strict inclusion/exclusion criteria of the randomized trials. Especially elderly patients, women, and patients with more and more severe comorbidities are underrepresented in
the clinical trials. We therefore aimed to summarize the importance of S/V in HF in terms of efficacy and safety in clinical trials
and daily clinical practice
Revisited Upper Reference Limits for Highly Sensitive Cardiac Troponin T in Relation to Age, Sex, and Renal Function
(1) Background: Highly sensitive cardiac troponin T (hs-cTnT) plays an essential role in the diagnosis of myocardial injury. The upper reference limit of the respective assay is generally applied, irrespective of age, renal function, or sex. We aimed to identify age-adjusted and sex-adjusted upper reference limits in relation to renal function in a large population-based cohort without cardiac diseases. (2) Methods: We included 5428 subjects of the population-based LIFE-Adult cohort, free of diagnosed cardiac diseases. Sex-adjusted and age-adjusted 99th percentiles for hs-cTnT in subjects with preserved renal function were obtained. (3) Results: The hs-cTnT values were higher in men of all age groups. In both sexes, an increasing age positively correlated with higher hs-cTnT values. Hs-cTnT weakly correlated with serum creatinine. The three-dimensional analysis of age, creatinine, and hs-cTnT showed no relevant additional effect of creatinine on hs-cTnT. In men aged above 60 and women above 70, the calculated 99th percentiles clearly exceeded the commonly applied thresholds. (4) Conclusion: Age and sex have a major impact on the serum concentration of hs-cTnT, while renal function does not. We propose to consider age-adjusted and sex-adjusted reference values
Comparison of cardiac, hepatic, and renal effects of arginine vasopressin and noradrenaline during porcine fecal peritonitis: a randomized controlled trial
INTRODUCTION: Infusing arginine vasopressin (AVP) in vasodilatory shock usually decreases cardiac output and thus systemic oxygen transport. It is still a matter of debate whether this vasoconstriction impedes visceral organ blood flow and thereby causes organ dysfunction and injury. Therefore, we tested the hypothesis whether low-dose AVP is safe with respect to liver, kidney, and heart function and organ injury during resuscitated septic shock. METHODS: After intraperitoneal inoculation of autologous feces, 24 anesthetized, mechanically ventilated, and instrumented pigs were randomly assigned to noradrenaline alone (increments of 0.05 microg/kg/min until maximal heart rate of 160 beats/min; n = 12) or AVP (1 to 5 ng/kg/min; supplemented by noradrenaline if the maximal AVP dosage failed to maintain mean blood pressure; n = 12) to treat sepsis-associated hypotension. Parameters of systemic and regional hemodynamics (ultrasound flow probes on the portal vein and hepatic artery), oxygen transport, metabolism (endogenous glucose production and whole body glucose oxidation derived from blood glucose isotope and expiratory 13CO2/12CO2 enrichment during 1,2,3,4,5,6-13C6-glucose infusion), visceral organ function (blood transaminase activities, bilirubin and creatinine concentrations, creatinine clearance, fractional Na+ excretion), nitric oxide (exhaled NO and blood nitrate + nitrite levels) and cytokine production (interleukin-6 and tumor necrosis factor-alpha blood levels), and myocardial function (left ventricular dp/dtmax and dp/dtmin) and injury (troponin I blood levels) were measured before and 12, 18, and 24 hours after peritonitis induction. Immediate post mortem liver and kidney biopsies were analysed for histomorphology (hematoxylin eosin staining) and apoptosis (TUNEL staining). RESULTS: AVP decreased heart rate and cardiac output without otherwise affecting heart function and significantly decreased troponin I blood levels. AVP increased the rate of direct, aerobic glucose oxidation and reduced hyperlactatemia, which coincided with less severe kidney dysfunction and liver injury, attenuated systemic inflammation, and decreased kidney tubular apoptosis. CONCLUSIONS: During well-resuscitated septic shock low-dose AVP appears to be safe with respect to myocardial function and heart injury and reduces kidney and liver damage. It remains to be elucidated whether this is due to the treatment per se and/or to the decreased exogenous catecholamine requirements
Improving exercise capacity and quality of life using non-invasive heart failure treatments: evidence from clinical trials
Endpoints of large-scale trials in chronic heart failure have mostly been defined to evaluate treatments with regard to hospitalizations and mortality. However, patients with heart failure are also affected by very severe reductions in exercise capacity and quality of life. We aimed to evaluate the effects of heart failure treatments on these endpoints using available evidence from randomized trials. Interventions with evidence for improvements in exercise capacity include physical exercise, intravenous iron supplementation in patients with iron deficiency, and – with less certainty – testosterone in highly selected patients. Erythropoiesis-stimulating agents have been reported to improve exercise capacity in anaemic patients with heart failure. Sinus rhythm may have some advantage when compared with atrial fibrillation, particularly in patients undergoing pulmonary vein isolation. Studies assessing treatments for heart failure co-morbidities such as sleep-disordered breathing, diabetes mellitus, chronic kidney disease and depression have reported improvements of exercise capacity and quality of life; however, the available data are limited and not always consistent. The available evidence for positive effects of pharmacologic interventions using angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, and mineralocorticoid receptor antagonists on exercise capacity and quality of life is limited. Studies with ivabradine and with sacubitril/valsartan suggest beneficial effects at improving quality of life; however, the evidence base is limited in particular for exercise capacity. The data for heart failure with preserved ejection fraction are even less positive, only sacubitril/valsartan and spironolactone have shown some effectiveness at improving quality of life. In conclusion, the evidence for state-of-the-art heart failure treatments with regard to exercise capacity and quality of life is limited and appears not robust enough to permit recommendations for heart failure. The treatment of co-morbidities may be important for these patient-related outcomes. Additional studies on functional capacity and quality of life in heart failure are required
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