Mixed Treatment Comparison Meta-Analysis of Aspirin,Warfarin, and New Anticoagulants for Stroke Prevention in Patients With Nonvalvular Atrial Fibrillation

Background

Warfarin and aspirin are used to prevent stroke in patients with atrial fibrillation (AF). There are inherent challenges with both treatments, including variable and inconsistent benefit and increased bleeding risks. The availability of new anticoagulants offers some alternatives.

Objective

A mixed treatment comparison meta-analysis to evaluate direct and indirect treatment data including aspirin, warfarin apixaban, dabigatran, edoxaban, and rivaroxaban for the prevention of primary or secondary stroke in patients with AF.

Methods

A comprehensive, systematic literature search was conducted to identify randomized trials comparing aspirin, warfarin, apixaban, dabigatran, edoxaban, and rivaroxaban in patients with AF requiring treatment for stroke prevention. Open-label and blinded designs were included if they evaluated any stroke or any bleeding event. Data on stroke and bleeding events were abstracted, verified, evaluated, scored, and entered into Aggregate Data Drug Information System version 1.16 to generate a mixed treatment comparison meta-analysis. Direct and indirect comparisons were evaluated, and we looked for inconsistency in closed loop structures. Data are reported as rate ratios with 95% credible intervals. In addition, we reviewed variance statistics and explored variance with node-splitting models.

Results

Our literature search yielded 30 articles, 21 of which were included. All treatments except aspirin reduced the risk of any stroke compared with placebo. Warfarin (0.43 [0.33–0.57]), apixaban (0.37 [0.27–0.54]), dabigatran (0.34 [0.21–0.57]), rivaroxaban (0.36 [0.22–0.60]), and aspirin with clopidogrel (0.73 [0.53–0.99]) were more protective than aspirin alone. Warfarin and the new anticoagulants were similar in the reduction of stroke, vascular death, and mortality. There was no difference in major bleeding between any treatment group. There were more nonmajor bleeding events when comparing warfarin and apixaban (1.83 [1.05–4.03]); no other differences between warfarin and the other new anticoagulants were found.

Conclusions

This mixed treatment comparison meta-analysis found similarity between warfarin and the new anticoagulants with the exception of one comparison, in which warfarin was associated with more non-major bleeding than apixaban. Thus, the new anticoagulants are therapeutically comparable when warfarin is inappropriate.     

Effects of an Inhibitor of Nitric Oxide Synthesis on Skin Wound Repair

Introduction:  The aim of this study was to compare the effects of Urgotul^® and other greasy dressings and interfaces on normal human dermal fibroblasts (NHDF) monolayers in vitro . The selected end points were the cell proliferation, the morphology of the extracellular matrix (ECM) upon dressing removal, and the structure of the underlying fibroblasts.
Materials and methods:  Equivalent pieces of each dressing were applied on NHDF monolayers for different times. Cell proliferation was measured via [3H] thymidine incorporation. Identical cultures were used to assess the dressing impact on the morphology of cells in culture after MTT staining and micro‐photographing. ECM morphology was shown by immunoflorescence, using an anticollagen I antibody. Effects on cell ultrastructure were documented by confocal laser microscopy after tubulin/actin double labelling.
Results:  Among the five tested greasy dressings and interfaces, only Urgotul^® showed a stimulating effect on the proliferation of NHDF. Two dressings did not modify proliferation and two other had cytostatic effects.
In addition, the lesions of the ECM upon dressing removal were clearly the lowest with Urgotul^®(low adherence to cellular surface and/or to extracellular matrix). The ultrastructure of the NHDF in direct contact with Urgotul^® was not significantly modified.
Conclusion:  Fibroblasts are the key cells of wound healing. The use of nonaggressive greasy gauzes and/or interfaces promoting cell proliferation should be of interest. Clinical evaluations are required to confirm these in vitro results.     

Inhibition of oxalate nephrolithiasis with Ammi visnaga (AI-Khillah)

We investigated the effect of Ammi visnaga seeds on experimentally – induced kidney stones – in male Wistar albino rats. Oxalate nephrolithiasis was experimentally induced by 3% glycolic acid (added in their diet) given for the period of four weeks. A highly significant amount of deposits were found in the kidneys, which were analyzed quantitatively. These deposits were mainly of calcium oxalate in composition.Daily oral (gavage) treatment with Ammi visnaga (500 mg/kg) highly reduced the incidence of nephrolithiasis (calcium oxalate deposition in the kidneys). Ammi visnaga seeds extract showed highly potent diuretic activity. The reduction in body weight, increase in kidneys weight, increase in water intake, decrease in urine output found in glycolic acid control group were prevented to various extent on Ammi visnaga treatment; and the values became to insignificant difference with control group. The changes in weights of liver, heart and lungs of the three groups were insignificant. Uraemia and hyperbilirubinaemia observed in glycolic acid control group were found to be ameliorated by Ammi visnaga seed extract treatment.     

Synoptic characteristics of dusty spring days over central and eastern Saudi Arabia

The synoptic characteristics of dusty spring days in central and eastern Saudi Arabia were analyzed using the aerosol index (AI) from the TOMS satellite and meteorological parameters from the NCEP/NCAR reanalysis dataset. The AI distributions were used to detect and classify dusty spring days into three classes (narrow, moderate, and wide spread). The synoptic features of the cases and classes demonstrated the common synoptic characteristics that represented the dusty spring cases. The strength of these common synoptic characteristics was found to increase with increasing dust severity. Specifically, as the following factors occurred, the cyclone located over the southern Arabian Peninsula deepened, the maximum wind at 250 hPa weakened and shifted northward, the instability over the northern Arabian Peninsula increased, the northerly wind generated, and the gradient of the 850-hPa potential temperature west of the cyclone increased; the severity of the dust class increased. The results were confirmed by examining three specific cases representing weak, moderate, and severe dust events.     

Metal–organic frameworks (MOFs) based nanofiber architectures for the removal of heavy metal ions

Environmental heavy metal ions (HMIs) accumulate in living organisms and cause various diseases. Metal–organic frameworks (MOFs) have proven to be promising and effective materials for removing heavy metal ions from contaminated water because of their high porosity, remarkable physical and chemical properties, and high specific surface area. MOFs are self-assembling metal ions or clusters with organic linkers. Metals are used as dowel pins to build two-dimensional or three-dimensional frameworks, and organic linkers serve as carriers. Modern research has mainly focused on designing MOFs-based materials with improved adsorption and separation properties. In this review, for the first time, an in-depth look at the use of MOFs nanofiber materials for HMIs removal applications is provided. This review will focus on the synthesis, properties, and recent advances and provide an understanding of the opportunities and challenges that will arise in the synthesis of future MOFs–nanofiber composites in this area. MOFs decorated on nanofibers possess rapid adsorption kinetics, a high adsorption capacity, excellent selectivity, and good reusability. In addition, the substantial adsorption capacities are mainly due to interactions between the target ions and functional binding groups on the MOFs–nanofiber composites and the highly ordered porous structure.

Metal–organic frameworks (MOFs) are promising and effective materials for removing heavy metal ions from contaminated water owing to their high porosity, remarkable physical and chemical properties, and high specific surface area.     

Photocatalysis and perovskite oxide-based materials: a remedy for a clean and sustainable future

The massive use of non-renewable energy resources by humankind to fulfill their energy demands is causing severe environmental issues. Photocatalysis is considered one of the potential solutions for a clean and sustainable future because of its cleanliness, inexhaustibility, efficiency, and cost-effectiveness. Significant efforts have been made to design highly proficient photocatalyst materials for various applications such as water pollutant degradation, water splitting, CO₂ reduction, and nitrogen fixation. Perovskite photocatalyst materials are gained special attention due to their exceptional properties because of their flexibility in chemical composition, structure, bandgap, oxidation states, and valence states. The current review is focused on perovskite materials and their applications in photocatalysis. Special attention has been given to the structural, stoichiometric, and compositional flexibility of perovskite photocatalyst materials. The photocatalytic activity of perovskite materials in different photocatalysis applications is also discussed. Various mechanisms involved in photocatalysis application from wastewater treatment to hydrogen production are also provided. The key objective of this review is to encapsulate the role of perovskite materials in photocatalysis along with their fundamental properties to provide valuable insight for addressing future environmental challenges.

Photocatalytic reaction for CO₂ reduction in presence of co-catalyst.     

Flexible Memory Device Composed of Metal-Oxide and Two-Dimensional Material (SnO2/WTe2) Exhibiting Stable Resistive Switching

Two-terminal, non-volatile memory devices are the fundamental building blocks of memory-storage devices to store the required information, but their lack of flexibility limits their potential for biological applications. After the discovery of two-dimensional (2D) materials, flexible memory devices are easy to build, because of their flexible nature. Here, we report on our flexible resistive-switching devices, composed of a bilayer tin-oxide/tungsten-ditelluride (SnO₂/WTe₂) heterostructure sandwiched between Ag (top) and Au (bottom) metal electrodes over a flexible PET substrate. The Ag/SnO₂/WTe₂/Au flexible devices exhibited highly stable resistive switching along with an excellent retention time. Triggering the device from a high-resistance state (HRS) to a low-resistance state (LRS) is attributed to Ag filament formation because of its diffusion. The conductive filament begins its development from the anode to the cathode, contrary to the formal electrochemical metallization theory. The bilayer structure of SnO₂/WTe₂ improved the endurance of the devices and reduced the switching voltage by up to 0.2 V compared to the single SnO₂ stacked devices. These flexible and low-power-consumption features may lead to the construction of a wearable memory device for data-storage purposes.     

Co(ii), Ni(ii), Cu(ii) and Cd(ii)-thiocarbonohydrazone complexes: spectroscopic,DFT, thermal,and electrical conductivity studies

New and stable coordinated compounds have been isolated in a good yield. The chelates have been prepared by mixing Co(ii), Ni(ii), Cu(ii), and Cd(ii) metal ions with (1E)-1-((6-methyl-4-oxo-4H-chromen-3-yl)methylene)thiocarbonohydrazide (MCMT) in 2 : 1 stoichiometry (MCMT : M²⁺). Various techniques, including elemental microanalyses, molar conductance, thermal studies, FT-IR, ¹H-NMR, UV-Vis, and XRD spectral analyses, magnetic moment measurements, and electrical conductivity, were applied for the structural and spectroscopic elucidation of the coordinating compounds. Further, computational studies using the DFT-B3LYP method were reported for MCMT and its metal complexes. MCMT behaves as a neutral NS bidentate moiety that forms octahedral complexes with general formula [M(MCMT)₂Cl(OH₂)]Cl·XH₂O (M = Cu²⁺; (X = ½), Ni²⁺, Co²⁺; (X = 1)); [Cd(MCMT)₂Cl₂]·½H₂O. There is good confirmation between experimental infrared spectral data and theoretical DFT-B3LYP computational outcomes where MCMT acts as a five-membered chelate bonded to the metal ion through azomethine nitrogen and thiocarbonyl sulphur donors. The thermal analysis is studied to confirm the elucidated structure of the complexes. Also, the kinetic and thermodynamic parameters of the thermal decomposition steps were evaluated. The measured optical band gap values of the prepared compounds exhibited semiconducting nature. AC conductivity and dielectric properties of the ligand and its complexes were examined, which showed that Cu(ii) complex has the highest dielectric constant referring to its high polarization and storage ability.

New and stable coordinated compounds have been isolated in a good yield.     

Drainage vs. non-drainage after cholecystectomy for acute cholecystitis: a retrospective study

Many surgeons practice prophylactic drainage after cholecystectomy without reliable evidence. This study was conducted to answer the question whether to drain or not to drain after cholecystectomy for acute calculous cholecystitis. A retrospective review of all patients who had cholecystectomy for acute cholecystitis in Aseer Central Hospital, Abha, Saudi Arabia, was conducted from April 2010 to April 2012. Data were extracted from hospital case files. Preoperative data included clinical presentation, routine investigations and liver function tests. Operative data included excessive adhesions, bleeding, bile leak, and drain insertion. Complicated cases such as pericholecystic collections, mucocele and empyema were also reported. Patients who needed therapeutic drainage were excluded. Postoperative data included hospital stay, volume of drained fluid, time of drain removal, and drain site problems. The study included 103 patients allocated into two groups; group A (n  =  38) for patients with operative drain insertion and group B (n  =  65) for patients without drain insertion. The number of patients with preoperative diagnosis of acute non-complicated cholecystitis was significantly greater in group B (80%) than group A (36.8%) (P < 0.001). Operative time was significantly longer in group A. All patients who were converted from laparoscopic to open cholecystectomy were in group A. Multivariate analysis revealed that hospital stay was significantly (P < 0.001) longer in patients with preoperative complications. There was no added benefit for prophylactic drain insertion after cholecystectomy for acute calculous cholecystitis in non-complicated or in complicated cases.