Predictors of pacemaker requirement in patients with implantable loop recorder and unexplained syncope: A systematic review and meta-analysis

Identifying the underlying cause of unexplained syncope is crucial for appropriate management of recurrent syncopal episodes. Implantable loop recorders (ILRs) have emerged as valuable diagnostic tools for monitoring patients with unexplained syncope. However, the predictors of pacemaker requirement in patients with ILR and unexplained syncope remain unclear. In this study, we shed light on these prognostic factors. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane CENTRAL were systematically searched until May 04, 2023. Studies that evaluated the predictors of pacemaker requirement in patients with implantable loop recorder and unexplained syncope were included. The "Quality In Prognosis Studies" appraisal tool was used for quality assessment. The pooled odds ratio (OR) with 95% confidence intervals (CIs) was calculated. The publication bias was evaluated using Egger's and Begg's tests. Ten studies (n = 4200) were included. Right bundle branch block (OR: 3.264; 95% CI: 1.907-5.588, p < .0001) and bifascicular block (OR: 2.969; 95% CI: 1.859-4.742, p < .0001) were the strongest predictors for pacemaker implantation. Pacemaker requirement was more than two times in patients with atrial fibrillation, sinus bradycardia and first degree AV block. Valvular heart disease, diabetes mellitus, and hypertension were also significantly more in patients with pacemaker implantation. Age (standardized mean difference [SMD]: 0.560; 95% CI: 0.410/0.710, p < .0001) and PR interval (SMD: 0.351; 95% CI: 0.150/0.553, p = .001) were significantly higher in patients with pacemaker requirement. Heart conduction disorders, atrial arrhythmias and underlying medical conditions are main predictors of pacemaker device implantation following loop recorder installation in unexplained syncopal patients.

Interaction between physicians and the pharmaceutical industry: A scoping review for developing a policy brief

Background

Payments to physicians by the pharmaceutical industry are common, but recent evidence shows that these payments influence physician prescribing behavior in the form of increased prescription of brand-name drugs, expensive and low-cost drugs, increased prescription of payer company drugs, etc. Considering that these payments increase drug costs for patients and health systems, there is a public interest in controlling them. Therefore, this study aimed to identify and propose policy options for managing physician-pharmaceutical industry interactions in the context of Iran's health system.

Methods

In the first phase, a systematic search was conducted to identify relevant policies and interventions in Web of Science, PubMed, and ProQuest databases from 2000 to 2022. Then, the opinions of the research team and an expert group (physicians, health policy and transparency experts, and industry representatives) were used to categorize the interventions and propose policy options along with their advantages, disadvantages, and implementation considerations.

Results

In the search, 579 articles were retrieved, and 44 articles were found suitable for the final analysis. Twenty-nine interventions and strategies were identified, and based on these; Five policy options were identified: prohibition, restriction, physician self-regulation, voluntary industry disclosure, and mandatory industry disclosure.

Conclusion

The proposed policies in our study include advantages, challenges, and implementation considerations based on up-to-date evidence that can help policymakers use them to manage COI in physician-pharmaceutical industry interactions in Iran's health system. A combination of measures seems to help manage COI: firstly, using self-regulating physicians and industry to institutionalize transparency, and in the next step, implementing mandatory industry disclosure policies and establishing restrictions on some financial interactions.

Multidimensional, High Precision Measurements of Beam Single Spin Asymmetries in Semi-inclusive π^{+} Electroproduction off Protons in the Valence Region

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7  GeV^{2}. In particular, the structure function ratio F_{LU}^{sinϕ}/F_{UU} has been determined, where F_{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.

Semi-inclusive deep inelastic scattering in Wandzura-Wilczek-type approximation

We present the complete cross-section for the production of unpolarized hadrons in semi-inclusive deep-inelastic scattering up to power-suppressed O(1/Q2) terms in the Wandzura–Wilczek-type approximation which consists in systematically assuming that q̅gq–terms are much smaller than q̅q–correlators. We compute all twist-2 and twist-3 structure functions and the corresponding asymmetries, and discuss the applicability of the Wandzura–Wilczek-type approximations on the basis of available data. We make predictions that can be tested by data from Jefferson Lab, COMPASS, HERMES, and the future Electron-Ion Collider. The results of this paper can be readily used for phenomenology and for event generators, and will help to improve our understanding of the TMD theory beyond leading twist. For more details see [1] or slides of Anatoly Efremov talk at https://indico.jinr.ru/getFile.py/access?contribId=25&sessionId=15&resId=0&materialId=slides&confId=433.

Determination of association constants between enantiomers of orciprenaline and methyl-beta-cyclodextrin as chiral selector by capillary zone electrophoresis using a partial filling technique

The principles for the determination of conditional association constants of enantiomers by capillary zone electrophoresis employing a partial filling technique (PFT) using methyl-beta-cyclodextrin as chiral selector is presented. Orciprenaline was used as a model compound. Partial filling is a separation technique, where different lengths of the chiral selector solution are introduced into the capillary to a final zone length shorter than the effective length of the capillary, prior to application of the solutes. Lengthening of the separation zone results in improving enantioresolution in addition to decreasing electrophoretic mobility of the enantiomers, because of longer interaction time between the solute and chiral selector. The degree of the reduction in electromobility depends on the affinity of the solute to the chiral selector, i.e. strength of the complex formed between the solute and cyclodextrin. The decrease in the electrophoretic mobility with increasing length of the separation zone is used for determination of the association constant. The association constants of the enantiomers of orciprenaline and the chiral selector were evaluated from the slope of the plot, observed electrophoretic mobility versus the ratio between the length of the separation zone and the effective length of the capillary. It was found that the association constants were independent of the chiral selector concentration. The mean values were 110 M(-1) and 160 M(-1) for respective enantiomer. Constants obtained by a conventional CE technique were in good agreement with those from the PFT experiments. The highest enantioselectivityy was obtained when about 50% of the solute was distributed to the selector phase.

Simultaneous separation and enantioresolution of racemic local anesthetic drugs by capillary zone electrophoresis with Tween 20 and methyl-beta-cyclodextrin as selectors, employing a double plug technique

A new approach for simultaneous chiral and achiral separations by capillary zone electrophoresis is described. Two adjacent selector plugs, consisting of Tween 20 as an achiral and methyl-beta-cyclodextrin (CD) as a chiral selector, are employed and four related local anesthetics are used as model compounds. The principles of the partial filling technique, whereby the capillary is filled with the chiral selector solution followed by the micellar solution at different plug lengths and concentrations, prior to application of the solutes, was employed. During the run both capillary ends were dipped in a simple buffer, i.e., one without additives. The two separation media worked independently without any interaction. Separation of the solutes and their enantiomers was regulated by adjusting both the concentration and plug length (PL) of the micellar solution in the capillary, employing methyl beta-CD as chiral selector either at 38 or 76 mM. The solutes were separated on the basis of their affinity towards the micellar phase before they reached the methyl-beta-CD plug for enantioseparation. In the absence of the micellar plug, the enantiomers of prilocaine overlapped those of bupivacaine. The solutes and their enantiomers were completely separated by employing two adjacent plugs consisting of 100 mM Tween 20 solution (PL approximately 10 cm) and methyl-beta-CD solution at either 38 or 76 mM (PL approximately 30 cm).

Effect of apomorphine infusion on dopamine synthesis rate relates to dopaminergic tone

The effects of apomorphine on the striatal L-[11C]DOPA influx rate was examined in anaesthetized Rhesus monkeys using positron emission tomography (PET). In comparison with baseline conditions, the addition of a continuous infusion of apomorphine produced decreases in the striatal L-[11C]DOPA influx rate in all the monkeys examined. The effect of apomorphine infusion also showed a dose-dependent trend. In individual monkeys, the magnitude of the effect showed a baseline dopaminergic tone-dependency; that is, the effect of apomorphine was most pronounced in monkeys with high baseline influx rates, and in monkeys with lower baseline values apomorphine induced a weaker effect. Studies of radiolabeled tracer and radiolabeled metabolites formed in plasma confirmed that apomorphine infusion did not induce any change in the peripheral elimination or metabolite formation of L-[11C]DOPA. The decreased striatal L-[11C]DOPA influx rate induced by apomorphine was interpreted as an agonist effect on dopamine autoreceptors regulating the dopamine synthesis rate. The observation of a baseline dopaminergic tone-dependent effect is in agreement with earlier results showing this influence on the striatal influx rate as measured with the tracer L-[11C]DOPA. A priori, it can be established that L-[11C]DOPA and PET provide a method not only to study the structural integrity of the presynaptic dopaminergic system but also to study the homeostasis-regulating mechanisms of this neurotransmitter system in vivo. The ability to measure condition-dependent effects in individuals should be of great importance in determining specific pathophysiological mechanisms underlying degenerative and functional disorders affecting the dopaminergic system.