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101.

Background

Type 2 diabetes is a chronic condition that requires pharmacotherapy interventions. Metformin and gliclazide are widely used drugs in monotherapy. However, their complementary action made utilization of the combination of these drugs an appealing approach.

Aims

The study compared major therapeutic potentials of combined metformin/gliclazide treatment over metformin monotherapy based on the following parameters: oxidative stress, lipid profile, and hepatorenal functions.

Subjects and methods

This is a comparative study was conducted from March 2015 to March 2016. The study screened 80 type 2 diabetic patients, of which 40 patients underwent combined metformin?+?gliclazide therapy (500?mg BD?+?80?mg OD, respectively). The other 40 were matched for age and duration of diabetes mellitus with the previous group and received metformin monotherapy (500?mg BD). The levels of fasting blood glucose (FBG), total glycated hemoglobin (HbA1c), lipid peroxidation, total antioxidant capacity, serum creatinine, aspartate and alanine transaminases, total cholesterol, triglycerides, high-density lipoproteins, and low-density lipoproteins were measured according to the standard methods.

Results

Oxidative stress, lipid profile, and hepatorenal functions were comparable in patients of both groups. However, patients on metformin treatment showed significantly lower levels of FBG [7.61 (6.70–8.89) mmol/L vs. 9.00 (7.30–10.68) mmol/L; P?=?.022] and HBA1c [7.00 (6.40–7.65)% vs. 8.20 (7.20–9.75)%; P?<?.001] compared to those on combined therapy.

Conclusion

Oxidative stress, lipids profile, and hepatorenal functions were not different in patients who were on combined metformin/gliclazide therapy and compared to those metformin alone. In contrast, glycemic control was poor in the diabetic patients undergoing combined therapy.  相似文献   
102.
103.

Objective

To assess community pharmacists’ knowledge, behaviors and experiences relating to Adverse Drug Reaction (ADR) reporting in Saudi Arabia.

Methods

A cross-sectional study was conducted using a validated self-administered questionnaire. A convenience sample of 147 community pharmacists working in community pharmacies in Riyadh, Saudi Arabia.

Results

The questionnaire was distributed to 147 pharmacists, of whom 104 responded to the survey, a 70.7% response rate. The mean age of participants was 29 years. The majority (n = 101, 98.1%) had graduated with a bachelorette degree and worked in chain pharmacies (n = 68, 66.7%). Only 23 (22.1%) said they were familiar with the ADR reporting process, and only 21 (20.2%) knew that pharmacists can submit ADR reports online. The majority of the participants (n = 90, 86.5%) had never reported ADRs. Reasons for not reporting ADRs most importantly included lack of awareness about the method of reporting (n = 22, 45.9%), misconception that reporting ADRs is the duty of physician and hospital pharmacist (n = 8, 16.6%) and ADRs in community pharmacies are simple and should not be reported (n = 8, 16.6%). The most common approach perceived by community pharmacists for managing patients suffering from ADRs was to refer him/her to a physician (n = 80, 76.9%).

Conclusion

The majority of community pharmacists in Riyadh have poor knowledge of the ADR reporting process. Pharmacovigilance authorities should take necessary steps to urgently design interventional programs in order to increase the knowledge and awareness of pharmacists regarding the ADR reporting process.  相似文献   
104.
105.
Purpose

Idiopathic junctional ectopic tachycardia (JET) is typically refractory to antiarrhythmic agents. Catheter ablation for JET is feasible but is associated with high risk of unintended atrioventricular (AV) block. There is limited data on the appropriate procedural technique and clinical outcomes with catheter ablation for idiopathic JET in adults.

Methods

This is a multicenter, retrospective study of all adult patients (age?≥?18 years) who underwent catheter ablation for idiopathic JET. Patient, procedural characteristics, and long-term outcomes were evaluated.

Results

Fifteen patients [radiofrequency ablation (RF)?=?14 and cryoablation?=?1) were treated with catheter ablation. The median age was 58 years with 67% males. All patients underwent mapping of the right atrium and the aortic cusps prior to energy delivery. The location of earliest activation in relation to the atrioventricular (AV) node was postero-superior in 73% (11/15), posterior in 13% (2/15), and superior in 13% (2/15) respectively. Acute success was 100%. Arrhythmia recurrence occurred in 53% (8/15) all of whom underwent a repeat ablation. High-grade AV block requiring permanent pacemaker occurred in 20% (3/15). At 12-month follow-up in the redo-ablation group, 37.5% (3/8) had recurrence of the arrhythmia two of which underwent a third ablation procedure.

Conclusion

Catheter ablation of idiopathic JET in adults is associated with a high rate of recurrence requiring multiple procedures and high risk of AV block requiring a permanent pacemaker. Mapping and ablation of the non-coronary cusp can be considered as the arrhythmia was controlled in 3 patients with no inadvertent AV block.

  相似文献   
106.
N,N-Substituted benzimidazole salts were successfully synthesized and characterized by 1H-NMR, 13C {1H} NMR and IR techniques, which support the proposed structures. Catalysts generated in situ were efficiently used for the carbonylative cross-coupling reaction of 2 bromopyridine with various boronic acids. The reaction was carried out in THF at 110 °C in the presence of K2CO3 under inert conditions and yields unsymmetrical arylpyridine ketones. All N,N-substituted benzimidazole salts 2a–i and 4a–i studied in this work were screened for their cytotoxic activities against human cancer cell lines such us MDA-MB-231, MCF-7 and T47D. The N,N-substituted benzimidazoles 2e and 2f exhibited the most cytotoxic effect with promising cytotoxic activity with IC50 values of 4.45 μg mL−1 against MDA-MB-231 and 4.85 μg mL−1 against MCF7 respectively.

The in situ prepared four component system Pd(OAc)2, 1,3-dialkylbenzimidazolium halides 2a–i and 4a–i, K2CO3 under CO atmosphere catalyses carbonylative cross-coupling reaction of 2-bromopyridine with various boronic acids to yield unsymmetrical arylpyridine ketones.  相似文献   
107.
Polymer nanocomposites used in underground cables have been of great interest to researchers over the past 10 years. Their preparation and the dispersion of the nanoparticles through the polymer host matrix are the key factors leading to their enhanced dielectric properties. Their important dielectric properties are breakdown strength, permittivity, conductivity, dielectric loss, space charge accumulation, tracking, and erosion, and partial discharge. An overview of recent advances in polymer nanocomposites based on LDPE, HDPE, XLPE, and PVC is presented, focusing on their preparation and electrical properties.  相似文献   
108.
109.
Cluster of differentiation 1c (CD1c)-dependent self-reactive T cells are abundant in human blood, but self-antigens presented by CD1c to the T-cell receptors of these cells are poorly understood. Here we present a crystal structure of CD1c determined at 2.4 Å revealing an extended ligand binding potential of the antigen groove and a substantially different conformation compared with known CD1c structures. Computational simulations exploring different occupancy states of the groove reenacted these different CD1c conformations and suggested cholesteryl esters (CE) and acylated steryl glycosides (ASG) as new ligand classes for CD1c. Confirming this, we show that binding of CE and ASG to CD1c enables the binding of human CD1c self-reactive T-cell receptors. Hence, human CD1c adopts different conformations dependent on ligand occupancy of its groove, with CE and ASG stabilizing CD1c conformations that provide a footprint for binding of CD1c self-reactive T-cell receptors.Cluster of differentiation 1 (CD1) proteins are a family of MHC class I-like glycoproteins that present lipid antigens to T cells. CD1 restricted T cells are abundant in humans and play important roles in host defense and immune regulation. Human CD1 proteins comprise five CD1 isoforms, CD1a, CD1b, CD1c, CD1d, and CD1e, which exhibit different intracellular trafficking behaviors and ligand binding preferences (1). Structurally, the main differences between these CD1 isoforms lie in the architecture of their lipophilic ligand binding grooves. Whereas all CD1 isoforms share a highly conserved A′ channel (or pocket) for binding C18–C26 acyl chains, specialization is provided by further connecting channels (27). In CD1a, the A′ channel is “fused” to a wide and shallow F′ channel, enabling binding of lipopeptides such as mycobacterial didehydroxymycobactin (DDM) (8). CD1b features a unique T′ tunnel that connects A′ and F′, thereby forming a “superchannel” for accommodating very long acyl chains (e.g., mycobacterial mycolates) (2, 4). CD1d, the only isoform also conserved in rodents, exhibits a two-branched ligand binding groove with two linear channels A′ and F′ connected near the main portal into the groove, known as the F′ portal. A similar two-branched arrangement of A′ and F′ is seen in CD1e, the only CD1 isoform not expressed on the cell surface. Compared with CD1d, CD1a, and CD1b, the portal into the groove in CD1e is widely exposed, consistent with its known role in lipid transfer processes inside lysosomes (6).CD1c presents foreign- (9, 10) as well as self-lipid antigens to T cells (11). Two recent crystal structures of human CD1c revealed a two-branched design similar to that of CD1d and CD1e, with two channels A′ and F′ connecting near the groove portal. In these structures, a mycobacterial phosphomycoketide (PM) or mannosyl-β1-phosphomycoketide (MPM) occupied the A′ channel, whereas an undefined short ligand was present in the F′ channel (7, 12). The spatial arrangement of these ligands in the CD1c groove was very similar to and virtually overlapping in 3D comparisons with that of alpha-galactosylceramide (αGC) in human CD1d (Fig. S1 A and B). Because CD1c and CD1d are known to traffic to the same intracellular compartments for antigen sampling (13), these CD1c-PM and CD1c-MPM structures did not readily explain how CD1c and CD1d could functionally differentiate. Furthermore, the F′ channel in both CD1c-PM and CD1c-MPM was widely open to solvent, which was strikingly different from known structures of CD1a, CD1b, and CD1d and reminiscent of CD1e (7, 12). Based on these facts we hypothesized that human CD1c might undergo substantial conformational transformations in the F′ channel region upon binding of more optimal ligands, with relevance for T-cell receptor binding.Open in a separate windowFig. S1.Published CD1d-αGC and CD1c-MPM structures show a similar arrangement of their bound ligands in both the A′ and F′ channel. (A) Comparison of the configurations of bound ligands in CD1d-αGC (PDB ID code 1ZT4), CD1c-MPM (PDB ID code 3OV6), and CD1c-SL (PDB ID code 5C9J). (B) Ligands bound to CD1d (PDB ID code 1ZT4) (αGC; shown in yellow) and CD1c (PDB ID code 3OV6) (MPM; shown in blue, and spacer lipid shown in cyan) are superimposed and shown in two different orientations.  相似文献   
110.
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