Cigarette Use and Cardiovascular Risk in Chronic Kidney Disease: An Unappreciated Modifiable Lifestyle Risk Factor

Tobacco use is a major modifiable cardiovascular risk factor in the general population and contributes to excess cardiovascular risk. Emerging evidence from large‐scale observational studies suggests that continued tobacco use is also an independent cardiovascular risk factor among patients with chronic kidney disease (CKD). The benefits of smoking cessation programs on improving the heath status of patients and reducing mortality are unequivocal in the general population. Despite this, there has been little effort in pursuing tobacco cessation programs in dialysis cohorts or those with lesser degrees of kidney impairment. Most of our attention to date has focused on the development of “kidney‐specific” interventions that reduce rates of renal disease progression and improve dialysis outcomes. The purpose of this current review is to describe the epidemiology of tobacco use among patients with CKD, draw attention to its negative impact on cardiovascular morbidity and mortality, and finally highlight potential strategies for successful intervention. We hope that this study heightens the importance of tobacco use in CKD, stimulates renewed interest in the barriers and challenges that exist in achieving smoking cessation, and endorses the efficacy of intervention strategies and the immeasurable benefits of quitting on cardiovascular and noncardiovascular outcomes.     

Capturing the stem cell paracrine effect using heparin‐presenting nanofibres to treat cardiovascular diseases

The mechanism for stem cell‐mediated improvement following acute myocardial infarction has been actively debated. We support hypotheses that the stem cell effect is primarily paracrine factor‐linked. We used a heparin‐presenting injectable nanofibre network to bind and deliver paracrine factors derived from hypoxic conditioned stem cell media to mimic this stem cell paracrine effect. Our self‐assembling peptide nanofibres presenting heparin were capable of binding paracrine factors from a medium phase. When these factor‐loaded materials were injected into the heart following coronary artery ligation in a mouse ischaemia‐reperfusion model of acute myocardial infarction, we found significant preservation of haemodynamic function. Through media manipulation, we were able to determine that crucial factors are primarily < 30 kDa and primarily heparin‐binding. Using recombinant VEGF‐ and bFGF‐loaded nanofibre networks, the effect observed with conditioned media was recapitulated. When evaluated in another disease model, a chronic rat ischaemic hind limb, our factor‐loaded materials contributed to extensive limb revascularization. These experiments demonstrate the potency of the paracrine effect associated with stem cell therapies and the potential of a biomaterial to bind and deliver these factors, pointing to a potential therapy based on synthetic materials and recombinant factors as an acellular therapy. Copyright © 2010 John Wiley & Sons, Ltd.     

Nucleotide binding by the erythrocyte transglutaminase/Gh protein, probed with fluorescent analogs of GTP and GDP

GTP is known to be a potent inhibitor of the protein crosslinking activity of transglutaminase (TG), probably the most abundant G protein in the human red cell. Nucleotide binding to TG was examined by fluorescence spectroscopy and anisotropy in mixtures of TG with methylanthraniloyl analogs of GTP and GDP. A characteristic feature was the appearance of a major energy transfer band (lambda(exc, max) = 290 nm, lambda(em) = 444 nm) from protein tryptophans to the bound nucleotides. Quenching of the bound fluorophore (lambda(exc) = 360 nm, lambda(em) = 444 nm) by acrylamide was barely different from that of free ligand. However, major changes were observed in anisotropy, which was used to demonstrate a facile exchange between bound and free nucleotides and to evaluate affinity constants for the binding of methylanthraniloyl GTP and GDP to TG.     

Corneal triple procedure: indications, complications, and outcomes: a developing country scenario

PURPOSE: We report the indications, complications, and outcomes of 104 corneal triple procedures in our institute. METHODS: Patient records of 104 consecutive cases of corneal triple procedure (penetrating keratoplasty with extracapsular cataract extraction and intraocular lens implantation) performed by experienced corneal surgeons between January 1992 and December 1997 were retrospectively reviewed. Relevant preoperative, operative, and postoperative data were collected. The outcome was assessed by the graft clarity and visual acuity at the last visit. Survival analysis of these grafts was determined by Kaplan-Meier method. RESULTS: Of 104 patients, 70 were men and 34 were women. Mean age of these patients was 48.5+/-17.1 years (range, 1-75 years). Corneal scarring with cataract was the reason for surgery in 69 (66.4%) cases. The intraoperative complications included vitreous upthrust in seven (6.9%) cases and posterior capsular dehiscence in three (2.9%) cases. The most common early postoperative complications were increased intraocular pressure in 19 (18.3%) and increased anterior chamber reaction in 25 (24%) cases. Posterior capsular opacification was seen in 26 (25%), graft reaction in 15 (14.4%), and secondary glaucoma in 15 (14.4%) cases. These formed the important late postoperative complications. The average postoperative follow-up was 23.7+/-17.6 months (range, 1.6-79.4 months); at which time 72% of the grafts remained clear. At last follow-up, 40% of patients had a visual acuity of > or = 20/40. CONCLUSIONS: Corneal scarring with cataract is the most common reason for triple procedure in this part of the world. This is a safe surgical procedure with good graft clarity and reasonable visual recovery.     

Testicular function in rats following immobilization stress

Stress is believed to influence male reproductive activity. Male rats were subjected to immobilization stress for 2 h/day for 30 days to assess the effects of stress on testicular function. Net mass of the testes, epididymes and the seminal vesicles, sperm morphology, number of epididymal sperms and percent progressive motility of the sperms were determined. Adrenal weights were significantly increased (P less than 0.05) in the stressed animals. There was no significant difference between the control and the stressed animals with respect to testicular and epididymal weight, level of sperm production, progressive motility, seminal vesicular weight and abnormal forms. Histological examination also revealed a similarity in the structure of seminiferous tubules, adequacy of cell types of developing germ cells, structure of Leydig cells and epididymal lumina in both the groups. This study demonstrated a lack of significant effect of immobilization stress on testicular function in rats.