Rate-Control or Rhythm-Contol: Where do we stand?

Atrial fibrillation is the most common sustained rhythm disturbance and its prevalence is increasing worldwide due to the progressive aging of the population. Current guidelines clearly depict the gold standard management of acute symptomatic atrial fibrillation but the best-long term approach for first or recurrent atrial fibrillation is still debated with regard to quality of life, risk of new hospitalizations, and possible disabling complications, such as thromboembolic stroke, major bleeds and death. Some authors propose that regaining sinus rhythm in all cases, thus re-establishing a physiologic cardiac function not requiring a prolonged antithrombotic therapy, avoids the threat of intracranial or extracranial haemorrhages due to Vitamin K antagonists or aspirin. On the contrary, advocates of a rate control approach with an accurate antithrombotic prophylaxis propose that such a strategy may avoid the risk of cardiovascular and non cardiovascular side effects related to antiarrhythmic drugs. This review aims to explore the state of our knowledge in order to summarize evidences and issues that need to be furthermore clarified

Direct analysis of sterols from dried plasma/blood spots by an atmospheric pressure thermal desorption chemical ionization mass spectrometry (APTDCI-MS) method for a rapid screening of Smith-Lemli-Opitz syndrome.

Here is proposed a rapid and sensitive method involving atmospheric pressure thermal desorption chemical ionization mass spectrometry (APTDCI-MS) for specific laboratory screening of the Smith– Lemli–Opitz syndrome (SLOS), an inherited defect of cholesterol biosynthesis. Biochemical findings in the blood of SLOS patients are low cholesterol (Chol), high 7- and 8-dehydrocholesterol (DHCs) levels and high DHCs/Chol ratios. The APTDCI proposed method is able to ionize sterols for qualitative and quantitative analysis directly from dried plasma/blood spots. Critical APTDCI parameters – desolvation gas flow and temperature – were optimized analyzing Chol, 7-DHC and cholesteryl stearate standards spotted onto a glass slide acquiring the full scan spectra in positive ion mode. Chol levels in dried plasma spots of unaffected controls (n ¼ 23) obtained by the proposed method were compared with those of the enzymatic method (y ¼ 0.9166x + 0.3811; r ¼ 0.8831) while Chol and DHCs of SLOS patients (n ¼ 9) were compared with the gas chromatography flame ionization detection (GC-FID) method (y ¼ 0.8214x + 0.7388; r ¼ 0.8288). The APTDCI-MS method is also able to differentiate normal from SLOS samples directly analyzing whole blood and washed red cells spotted on paper. In conclusion, the intrinsic analytical high-throughput of APTDCI-MS method for sterol analysis could be useful to screen SLO syndrome

The effect of age on daily positive emotions and work behaviors

This study draws on socioemotional selectivity and person–job fit theories to investigate the emotional bases for age-related differences in daily task crafting and in-role performance. We tested a mediation model in which age is related to positive emotions that in turn predict task crafting and in-role performance. A total of 256 people working in multiple organizations participated in a 5-day diary study. Multilevel modeling showed that, at the person level of analysis, age is significantly and positively related to positive emotions and task crafting and, via crafting, to in-role performance. No significant mediation of high- and low-arousal positive emotions was found between age and task crafting. However, at the day level of analysis, high-arousal positive emotions are positively related to task crafting, and this in turn is positively related to in-role performance. These findings make important theoretical contributions to understanding within-person processes associated with employee age in addition to more traditional between-person factors. They also have implications for managing an age-diverse workforce by means of job crafting.info:eu-repo/semantics/acceptedVersio

Relationship between blood remifentanil concentration and stress hormone levels during pneumoperitoneum in patients undergoing laparoscopic cholecystectomy

The effect of remifentanil on stress response to surgery is unclear. However, there are not clinical studies investigating the relationship between blood remifentanil concentrations and stress hormones. Therefore, the aim of the present study was to assess the association between blood remifentanil concentrations measured after pneumoperitoneum and cortisol (CORT) or prolactin (PRL) ratio (intraoperative/preoperative value), in patients undergoing laparoscopic cholecystectom

A comprehensive study of infrared OH prompt emission in two comets. I. Observations and effective g-factors

We present high-dispersion infrared spectra of hydroxyl (OH) in comets C/2000 WM1 (LINEAR) and C/2004 Q2 (Machholz), acquired with the Near Infrared Echelle Spectrograph at the Keck Observatory atop Mauna Kea, Hawaii. Most of these rovibrational transitions result from photodissociative excitation of H_2O giving rise to OH "prompt" emission. We present calibrated emission efficiencies (equivalent g-factors, measured in OH photons s^(-1) [H_2O molecule]^(-1)) for more than 20 OH lines sampled in these two comets. The OH transitions analyzed cover a broad range of rotational excitation. This infrared database for OH can be used in two principal ways: (1) as an indirect tool for obtaining water production in comets simultaneously with the production of other parent volatiles, even when direct detections of H_2O are not available; and (2) as an observational constraint to models predicting the rotational distribution of rovibrationally excited OH produced by water photolysis

Cometary diversity and cometary families

Comets are classified from their orbital characteristics into two separate classes: nearly-isotropic, mainly long-period comets and ecliptic, short-period comets. Members from the former class are coming from the Oort cloud. Those of the latter class were first believed to have migrated from the Kuiper belt where they could have been accreted in situ, but recent orbital evolution simulations showed that they rather come from the trans-Neptunian scattered disc. These two reservoirs are not where the comets formed: they were expelled from the inner Solar System following interaction with the giant planets. If comets formed at different places in the Solar System, one would expect they show different chemical and physical properties. In the present paper, I review which differences are effectively observed: chemical and isotopic compositions, spin temperatures, dust particle properties, nucleus properties... and investigate whether these differences are correlated with the different dynamical classes. The difficulty of such a study is that long-period, nearly-isotropic comets from the Oort cloud are better known, from Earth-based observations, than the weak nearly-isotropic, short-period comets. On the other hand, only the latter are easily accessed by space missions.Comment: Proceedings of the XVIIIemes Rencontres de Blois: Planetary Science: Challenges and Discoveries, 28th May - 2nd June 2006, Blois, Franc

Random Graph-Homomorphisms and Logarithmic Degree

A graph homomorphism between two graphs is a map from the vertex set of one graph to the vertex set of the other graph, that maps edges to edges. In this note we study the range of a uniformly chosen homomorphism from a graph G to the infinite line Z. It is shown that if the maximal degree of G is `sub-logarithmic', then the range of such a homomorphism is super-constant. Furthermore, some examples are provided, suggesting that perhaps for graphs with super-logarithmic degree, the range of a typical homomorphism is bounded. In particular, a sharp transition is shown for a specific family of graphs C_{n,k} (which is the tensor product of the n-cycle and a complete graph, with self-loops, of size k). That is, given any function psi(n) tending to infinity, the range of a typical homomorphism of C_{n,k} is super-constant for k = 2 log(n) - psi(n), and is 3 for k = 2 log(n) + psi(n)

Plasma levels of conjugated bile acids in newborns after a short period of parenteral nutrition.

Background: Patients receiving parenteral nutrition (PN) frequently exhibit liver dysfunction. The authors previously reported that plant sterols of lipid emulsions added to the nutritional solution of newborns receiving PN accumulate in plasma and cell membranes and may contribute to the development of cholestasis. Conjugated bile acids (BA) have been shown to be useful markers of cholestasis. Plasma levels of several BA in newborns were quantified after administration of PN for less than 2 weeks. Methods: Plasma samples from 15 healthy control infants (CN), 22 patients who had received PN for 3-15 days (T1), and 9 patients scheduled to receive PN (T0) were analyzed. After a simple extraction procedure, plasma BA were analyzed by liquid chromatography-tandem mass spectrometry using a quantitative isotope dilution method. Results: The concentrations of BA did not differ significantly between controls and patients before PN (CN vs T0), with the exception of glycocholic acid (GCA; 2.30 ± 2.60 ??M vs 7.29 ± 5.39 ??M, respectively). There was a significant difference in several BA between controls and patients after PN (2.30 ± 2.60 ??M vs 7.61 ± 6.46 ??M for GCA, respectively; 4.02 ± 3.49 ??M vs 11.88 ± 11.05 ??M for taurocholic acid [TCA], respectively; and 4.81 ± 3.49 ??M vs 13.58 ± 12.22 ??M for taurochenodeoxycholic + taurodeoxycholic + tauroursodeoxycholic acids [TCDCA+TDCA+TUDCA], respectively). Conclusions: In newborns receiving PN, a short period of PN is associated with an early increase of some conjugated BA. These results suggest that GCA, TCA, and TCDCA+TDCA+TUDCA levels could be used as early markers of PN-related cholestasis

Sterol profiles in plasma and erythrocyte membranes in patients with Smith-Lemli-Opitz syndrome: a six-year experience

Background: This study reports our experience over the last six years in the diagnosis of Smith-Lemli-Opitz syndrome and other inborn errors of cholesterol biosynthesis. Methods: Gas chromatography/mass spectrometry was used to obtain sterol profiles in plasma and erythrocyte membranes of suspected patients. Results: Plasma sterol reference values calculated in unaffected subjects (ns276) were in agreement with those previously reported. Among patients investigated from 2005 to 2010, we report 16 patients affected by Smith-Lemli-Opitz syndrome, three of whom represent new cases and 13 of whom were follow-up patients. In this period we also identified a new case of chondrodysplasia punctata 2 X-linked. The estimated incidence obtained for Smith-Lemli-Opitz syndrome was 1:93 suspected patients (1.08%). We also studied the effect of storage on the dehydrocholesterols/ cholesterol ratio in plasma and erythrocyte membranes of patients affected by Smith-Lemli-Opitz syndrome stored at –208C for up to 22 and 20 months, respectively. A significant negative linear correlation between storage time and the dehydrocholesterols/cholesterol ratio was identified in both plasma and erythrocyte membranes. The decrease in the dehydrocholesterols/cholesterol ratio in erythrocyte membranes was at least two-fold higher than in plasma. Conclusions: The results of this study may be helpful for diagnosis and interpretation of data in patients with findings suggestive of a cholesterol biosynthesis defect