Atrial fibrillation: Epidemiology, pathophysiology, and clinical complications (literature review).

The last three decades have been characterized by an exponential increase in knowledge and advances in the clinical management of atrial fibrillation. The purpose of the study is to provide an overview of the pathogenesis of nonvalvular atrial fibrillation and a comprehensive investigation of the epidemiological data associated with various risk factors for atrial fibrillation. The leading research methods are analysis and synthesis, comparison, observation, induction and deduction, and grouping method. Research has shown that old age, male gender, and European descent are important risk factors for developing atrial fibrillation. Other modifiable risk factors include a sedentary lifestyle, smoking, obesity, diabetes mellitus, obstructive sleep apnea, and high blood pressure predisposing to atrial fibrillation, and each has been shown to induce structural and electrical atrial remodeling. Both heart failure and myocardial infarction increase the risk of developing atrial fibrillation and vice versa creating feedback that increases mortality. The review is a comprehensive study of the epidemiological data linking nonmodifiable and modifiable risk factors for atrial fibrillation, and the pathophysiological data supporting the relationship between each risk factor and the occurrence of atrial fibrillation. This may be necessary for the practice of the treatment of the cardiac system.

Comparative Effectiveness and Safety of Cryoablation Versus Radiofrequency Ablation Treatments for Persistent Atrial Fibrillation.

The purpose of this study was to compare the effectiveness and safety of 2 strategies for catheter treatment of patients with persistent atrial fibrillation in the long-term period, using cardiac implantable loop recorders. The research is a prospective, randomized, controlled study designed to compare the results of modern catheter technologies in patients with persistent atrial fibrillation. The study included 127 patients with persistent atrial fibrillation in the last 6 months before inclusion in the study, for whom at least 2 antiarrhythmic drugs of class I to III were not effective. By random distribution, 50 patients were included in group 1; they underwent cryoballoon ablation, using a cryoballoon of the second generation. Group 2 also included 50 patients who underwent radiofrequency ablation, where a catheter was used to control the contact force. Cardiac implantable loop electrocardiogram recorders were implanted in all patients after surgery. The average duration of follow-up was 36 months. The primary end point of efficacy occurred in 15 patients in the group with cryoballoon ablation and 14 patients in the group with radiofrequency ablation. In conclusion, the primary effectiveness was relatively the same in the groups; yet, in the long-term period, the superiority of radiofrequency ablation using catheters with pressure control was noted, but the difference in results was statistically insignificant (p <0.672) and there was no significant difference between the 2 methods in terms of overall safety.

The efficacy and safety of cryoballoon catheter ablation in patients with paroxysmal atrial fibrillation.

BACKGROUND: Electrical isolation of pulmonary vein ostia is an established therapy for paroxysmal atrial fibrillation. AIMS: The purpose of this study is to evaluate the long-term efficacy and safety of cryoballoon catheter ablation in paroxysmal atrial fibrillation with normal anatomy of the left atrium. METHODS: Two hundred fifteen consecutive patients were included in the study (from November 2014 to November 2016). All the patients had symptoms of paroxysmal atrial fibrillation resistant to antiarrhythmic drugs and underwent pulmonary vein cryoisolation using second-generation cryoballoons. Standard "single-shot" cryoballoon exposures were used alternately for each of the four pulmonary veins. The endpoint of the ablation procedure was the electrical isolation of each pulmonary vein. RESULTS: Sixty-nine patients had stable atrial fibrillation recurrences and left atrial flutter with 30 of 69 patients having atrial fibrillation paroxysms during the first year after primary ablation. Repeated ablation was performed within 6-12 months after the first ablation. In 39 of 69 cases, arrhythmia recurrences were registered during the second and third year after the first ablation. These patients underwent repeated ablation within 12-36 months after the first ablation. In 98% of the patients, no disease progression with a transition to a persistent form of atrial fibrillation was observed. During the mean 5-year follow-up period, no disease progression with the transition to persistent forms of atrial fibrillation was observed. CONCLUSIONS: It was concluded that in patients with paroxysmal atrial fibrillation, with normal left atrium anatomy and no risk factors, it can be controlled with single pulmonary vein isolation without additional atrial substrate modification.

Fight against COVID-19: The case of antiviral surfaces.

The COVID-19 pandemic is the largest global public health outbreak in the 21st century so far. Based on World Health Organization reports, the main source of SARS-CoV-2 infection is transmission of droplets released when an infected person coughs, sneezes, or exhales. Viral particles can remain in the air and on the surfaces for a long time. These droplets are too heavy to float in air and rapidly fall down onto the surfaces. To minimize the risk of the infection, entire surrounding environment should be disinfected or neutralized regularly. Development of the antiviral coating for the surface of objects that are frequently used by the public could be a practical route to prevent the spread of the viral particles and inactivation of the transmission of the viruses. In this short review, the design of the antiviral coating to combat the spread of different viruses has been discussed and the technological attempts for minimizing the coronavirus outbreak have been highlighted.

Prediction of arrhythmia recurrence after atrial fibrillation ablation in patients with normal anatomy of the left atrium.

BACKGROUND: Enlarged left atrium is an established predictor of atrial fibrillation recurrence after pulmonary vein isolation but arrhythmia recurrence is also observed in patients with normal anatomy of the left atrium. The aim of the study is to evaluate arrhythmia recurrence predictors in patients with normal anatomy of the left atrium. METHODS: The study included 182 patients with normal anatomy of the left atrium who underwent pulmonary vein isolation using catheter ablation. Various parameters were also compared, including age, gender, history of arrhythmia, arterial hypertension, concomitant coronary pathology, echocardiography findings, such as mitral valve and tricuspid valve regurgitation and procedure parameters, between patients with and without relapses. Statistical analysis was performed using the IBM SPSS Statistics-19 software. RESULTS: Transthoracic echocardiography was performed by independent specialists with extensive experience. Trans-esophageal echocardiography was performed before each ablation procedure. Standard trans-septal puncture was performed under fluoroscopic control. Radiofrequency ablation was performed in the ipsilateral pulmonary vein antrum with a wide capture of nearby lung tissue. CONCLUSIONS: It was concluded that the tricuspid valve regurgitation and arterial hypertension correlate with atrial fibrillation recurrence after pulmonary vein isolation in patients with normal left atrial anatomy.

Lower extremity arteries.

Lower extremity arteries play vital role of supplying blood to the extremity bone, muscles, tendons and nerves to maintain the mobility of the body. These arteries may get involved with a number of disease processes which restrict the optimal functioning of the limb. The knowledge of various diseases, clinical presentation, appearance on various imaging modalities and segments of involvement helps one to clinch the diagnosis. It is of paramount importance for imaging clinician to apply the correct imaging tool based on the clinical question which is facilitated by know how of the advantages and limitation of each of these imaging modalities. This article focuses on lower extremity arteries, its anatomy, various imaging modalities and common disease conditions affecting the lower limb arteries.

Fluorinated MOF platform for selective removal and sensing of SO2 from flue gas and air.

Conventional SO2 scrubbing agents, namely calcium oxide and zeolites, are often used to remove SO2 using a strong or irreversible adsorption-based process. However, adsorbents capable of sensing and selectively capturing this toxic molecule in a reversible manner, with in-depth understanding of structure-property relationships, have been rarely explored. Here we report the selective removal and sensing of SO2 using recently unveiled fluorinated metal-organic frameworks (MOFs). Mixed gas adsorption experiments were performed at low concentrations ranging from 250 p.p.m. to 7% of SO2. Direct mixed gas column breakthrough and/or column desorption experiments revealed an unprecedented SO2 affinity for KAUST-7 (NbOFFIVE-1-Ni) and KAUST-8 (AlFFIVE-1-Ni) MOFs. Furthermore, MOF-coated quartz crystal microbalance transducers were used to develop sensors with the ability to detect SO2 at low concentrations ranging from 25 to 500 p.p.m.

Room-temperature synthesis of a new stable (N2H4)WO3 compound: a route for hydrazine trapping.

A new (N2H4)WO3 compound has been obtained by mixing WO3 and aqueous hydrazine solution at room temperature for 24 h. The reaction is catalyzed by the presence of lithium. X-ray, synchrotron and neutron diffraction techniques have shown that the material crystallizes in trigonal space group P3221 (No. 154). Chains of distorted WO4 tetrahedra extend along the a axis of the unit cell, linked by a corner-sharing oxygen atom: the N2H4 are in the voids between them. The thermal characterization shows that this new compound is stable up to 220°C, greatly beyond the boiling point of N2H4 (114°C); thus making it a promising candidate for catalysis or trapping applications.

Effect of laboratory-isolated Lactobacillus plantarum LGFCP4 from gastrointestinal tract of guinea fowl on growth performance, carcass traits, intestinal histomorphometry and gastrointestinal microflora population in broiler chicken.

The study aimed to investigate the effect of feed supplements, viz Lactobacillus plantarum LGFCP4 (laboratory isolate from GIT of Guinea fowl), Lactobacillus acidophilus (NCDC, Karnal) and in-feed antibiotic bacitracin methylene disalicylate (BMD) on growth performance, FCR, carcass traits and immune organs weight, intestinal histomorphometry and gastrointestinal microflora population in broiler chickens. In a completely randomized design, CARIBRO-Dhanraja broiler chicks (n = 160) were used with four treatment groups. During the entire experimental duration of 35 days, treatment groups were provided with different dietary treatments (T1 - basal diet (negative control), T2 - antibiotic growth promoter BMD 20 g/100 kg feed (positive control), T3 - 1 × 108  cfu of L. acidophilus/gm-fermented feed +MOS 1 g/kg feed and T4 - 1 × 108  cfu of laboratory-isolated L. plantarum LGFCP4/gm-fermented feed+ MOS 1 g/kg feed. After 35 days of experimental period, no significant results have been observed in different growth performance traits among treatment groups. Cut-up parts and edible organs' weight remained unaffected by dietary supplementation, whereas weight of immune organs were significantly higher (p < 0.05) in L. plantarum LGFCP4-supplemented group. At the end of feeding trial, significantly (p < 0.05) lower E. coli count was observed in crop of T4 birds, while in ileum, T2 and T3 showed lower count. In caeca, T2 group showed lowest E. coli count. Salmonella count in crop and ileum was significantly (p < 0.05) low in T3 and T4, while in caeca, T2 group showed lowest count. In terms of histomorphometry, duodenal villous height (VH), crypt depth (CD) and VH:CD ratio were higher for T3 and T4 and lowest values were obtained for T2 group. The results of the study showed that L. plantarum LGFCP4 isolated from GIT of guinea fowl can effectively replace in-feed antibiotic growth promoters in broiler diets by altering intestinal villi morphology and improving the gut health by reducing the pathogenic microbial load.

A metal-organic framework-based splitter for separating propylene from propane.

The chemical industry is dependent on the olefin/paraffin separation, which is mainly accomplished by using energy-intensive processes. We report the use of reticular chemistry for the fabrication of a chemically stable fluorinated metal-organic framework (MOF) material (NbOFFIVE-1-Ni, also referred to as KAUST-7). The bridging of Ni(II)-pyrazine square-grid layers with (NbOF5)(2-) pillars afforded the construction of a three-dimensional MOF, enclosing a periodic array of fluoride anions in contracted square-shaped channels. The judiciously selected bulkier (NbOF5)(2-) caused the looked-for hindrance of the previously free-rotating pyrazine moieties, delimiting the pore system and dictating the pore aperture size and its maximum opening. The restricted MOF window resulted in the selective molecular exclusion of propane from propylene at atmospheric pressure, as evidenced through multiple cyclic mixed-gas adsorption and calorimetric studies.

Screening of Lactobacillus isolates from gastrointestinal tract of guinea fowl for probiotic qualities using in vitro tests to select species-specific probiotic candidates.

A total of 32 Lactobacillus isolates, 8 each from the crop (LGFCP1-LGFCP8), proventriculus (LGFP9-LGFP16), ileum (LGFI17-LGFI24) and caeca (LGFCM25-LGFCM32) were isolated from 25 adult guinea fowl (Pearl variety), 22-28 weeks of age, and characterised morphologically, physiologically, biochemically and by molecular methods. Isolates were screened for their probiotic quality using range of in vitro tests: aggregation test, cell surface hydrophobicity, resistance to bile salts and acidic conditions, enzymatic tests and coaggregation and antagonistic test. Based on in vitro test results and a novel scoring method, the two best isolates were selected and partial 16S rRNA sequencing was done. BLAST (Basic Local Alignment Search Tool) analysis of sequence of isolate LGFCP4 showed 99% genetic identity with Lactobacillus plantarum and LGFP16 with Lactobacillus reuteri. The study shows that these two microbial agents may be suitable as potential probiotic candidates in guinea fowl, as well as in a feed supplement for other poultry species.

Poly[bis(µ-purin-9-ido-κ(2)N(7):N(9))zinc].

In the title compound, [Zn(C(5)H(3)N(4))(2)], the Zn(II) cation is in a nearly regular tetra-hedral coordination by purinate ligands. Each purinate ligand chelates two Zn(II) cations through two imidazole N atoms of the purinate anion ligand, leading to the formation of a three-dimensional network.

7,9-Bis(hy-droxy-meth-yl)-7H-purine-2,6,8(1H,3H,9H)trione.

The structure of the title uric acid derivative, C(7)H(8)N(4)O(5), from human kidney stones, is characterized by the C and O atoms of one of the two hy-droxy-methyl groups being disordered nearly equally over three different sites. In the crystal, mol-ecules are connected by a three-dimensional hydrogen-bonding scheme though they look stacked in planes nearly parallel to ([Formula: see text]04).

A new organic-inorganic hybrid oxyfluorotitanate [Hgua]2·(Ti5O5F12) as a transparent UV filter.

A new generation UV absorber is obtained by microwave-heating-assisted hydrothermal synthesis: [Hgua](2)·(Ti(5)O(5)F(12)). The structure of this hybrid titanium(IV) oxyfluoride is ab initio determined from powder X-ray data by combining a direct space method, Rietveld refinement [orthorhombic, Cmm2, a = 22.410(1) Å, b = 11.191(1) Å, c = 3.802(1) Å], and density functional theory geometry optimization. The three-dimensional network is built up from infinite inorganic layers (∞)(Ti(5)O(5)F(12)) separated by guanidinium cations. The theoretical optical gap (3.2 eV) estimated from density of state calculations is in good agreement with the experimental gap (3.3 eV) obtained by UV-vis diffuse reflectivity. The optical absorption is mainly due to O(2p) → Ti(3d) and F(2p) → Ti(3d) transitions at higher energies. The refraction index is low in the visible range (n ≈ 1.9) compared to that of TiO(2) and, consequently, [Hgua](2)·(Ti(5)O(5)F(12)) shows a good transparency adapted to UV shielding. Under UV irradiation at 254 nm for 40 h, the white microcrystalline powder turns to light purple-gray. This color change is caused by the reduction of Ti(IV) to Ti(III), confirmed by magnetic measurements.

Diethyl-enetriaminium hexa-fluorido-titanate(IV) fluoride.

The title compound, (C(6)H(21)N(4))[TiF(6)]F, was synthesized by the reaction of TiO(2), tris-(2-amino-ethyl)amine, HF and ethanol at 463 K in a microwave oven. The crystal structure consists of two crystallographically independent [TiF(6)](2-) anions, two fluoride anions and two triply-protonated tris-(2-amino-ethyl)-amine cations. The Ti atoms are coordinated by six F atoms within slightly distorted octa-hedra. The anions and cations are connected by inter-molecular N-H⋯F hydrogen bonds.