Impact of oxidative stress on lung diseases

Reactive oxygen species (ROS) are products of normal cellular metabolism and are known to act as second messengers. Under physiological conditions, ROS participate in maintenance of cellular 'redox homeostasis' in order to protect cells against oxidative stress through various redox-regulatory mechanisms. Overproduction of ROS, most frequently due to excessive stimulation of either reduced nicotinamide adenine dinucleotide phosphate by cytokines or the mitochondrial electron transport chain and xanthine oxidase, results in oxidative stress. Oxidative stress is a deleterious process that leads to lung damage and consequently to various disease states. Knowledge of the mechanisms of ROS regulation could lead to the pharmacological manipulation of antioxidants in lung inflammation and injury.     

Neuropeptide Y: identification of the binding site

Based on the hypothetical 3D structure of neuropeptide Y (NPY), NPY 1-4-Aca-25-36, a 17 amino acid analogue, has been synthesized replacing the sequence NPY 5-24 by ε-aminocaproic acid (Aca). This low-molecular weight deletion analogue showed nearly comparable receptor affinity to NPY. In order to elucidate the structural requirements for receptor recognition each amino acid of 1-4-Aca-25-36 was exchanged by its D-enantiomer, glycine and L-alanine. In addition distinct amino acids were replaced by closely related residues. Multiple peptide synthesis was applied using Fmoc-strategy and BOP activation. Binding assay was performed on rabbit kidney membrane preparations. The results of structure affinity studies suggest that the C-terminal tetrapeptide NPY 33-36 is essential for receptor recognition.     

Skin barrier function recovery after diamond microdermabrasion

Microdermabrasion is a popular method for facial rejuvenation and is performed worldwide. Despite its extensive usage, there are few publications on skin barrier change after microdermabrasion and none concerning diamond microdermabrasion. Our object was to see changes in transepidermal water loss (TEWL), hydration and erythema of the face following diamond microdermabrasion. Twenty-eight patients were included in this spilt face study. TEWL, stratum corneum hydration and the degree of erythema were measured from the right and left sides of the face (forehead and cheek) at baseline. One side of the face was treated with diamond microdermabrasion and the other side was left untreated. Measurements were taken right after the procedure and repeated at set time intervals. Diamond microdermabrasion was associated with a statistically significant increase in TEWL immediately after the procedure and at 24 h. However, on day 2, levels of TEWL were back to baseline. An increase in hydration and erythema was observed right after microdermabrasion, but both returned to baseline on day 1. The results show that skin barrier function of the forehead and cheek recovers within 2 days of diamond microdermabrasion. Diamond microdermabrasion performed on a weekly basis, as presently done, is expected to allow sufficient time for the damaged skin to recover its barrier function in most parts of the face.     

Use of an Implantable Cardioverter Defibrillator in an Eight-Month-Old Infant with Ventricular Fibrillation Arising from a Myocardial Fibroma

We report our experience with use of a ICD in a 7-month-old infant who presented with VF. We utilized an epicardial patch and active generator in the abdomen. Development of mediastinitis required explantation and eventual replacement with a subcutaneous patch and active generator in the abdomen.     

Signal transduction pathway in human middle ear cholesteatoma

Phospholipase C-gamma1 plays a central role in signal transduction, and it is important in cellular growth, differentiation, and proliferation. Human cholesteatoma in the middle ear is characterized by the presence of a keratinizing epithelium that is believed to have hyperproliferative properties. The purpose of this study is to elucidate the distribution of phospholipase C-gamma1 in cholesteatoma matrix and deep meatal skin with Western blot analysis and immunohistochemistry. In conclusion, overexpression of phospholipase C-gamma1 in cholesteatoma matrix suggests a possible derangement of enhanced growth signal transduction in keratinocytes.     

The Effect and Safety of the Antithrombotic Therapies in Patients with Atrial Fibrillation and CHADS2 Score 1

Anticoagulation in CHADS₂ Score 1 . Background: The revised ACC/AHA/ESC 2006 guideline recommends either aspirin or warfarin for the prevention of ischemic stroke in patients with atrial fibrillation (AF) in CHADS₂ score 1. We hypothesized that warfarin is superior to aspirin therapy for the prevention of stroke without increasing bleeding complication in AF patients with CHADS₂ score 1. Methods and Results: Among 1,502 patients (mean 62.4 ± 13.8 years old, male 65.4%) who were treated for nonvalvular AF without previous stroke, the number of patients with CHADS₂ score 1 was 422 (62.9 ± 10.7 years old, male 290 [68.7%]) and their antithrombotic therapies were as follows: warfarin (n = 143), aspirin (n = 124), other antiplatelet (n = 45), and no antithrombosis (none: n = 110). We reviewed the incidences of ischemic stroke, mortality, and bleeding complications during the follow‐up period. Results were: (1) during 22.3 ± 17.8 months of follow‐up, the incidence of ischemic stroke was significantly lower in warfarin (6 patients, 4.2%, mean international normalized ratio [INR] 2.0 ± 0.5 IU) than in aspirin (16 patients, 12.9%, P = 0.008) than none (23 patients, 20.9%, P < 0.001) without differences in all‐cause mortality. (2) The incidence of major bleeding (decrease in hemoglobin ≥2 g/dL, requiring hospitalization or red blood cell transfusion ≥2 pints) was not different between warfarin (2.1%) and aspirin (0.8%, P = NS), but minor bleeding was more common in warfarin (10.5%) than in aspirin (2.4%, P = 0.007). Conclusion: In AF patients with CHADS₂ score 1, warfarin was better to prevent ischemic stroke than aspirin without increasing the incidence of major bleeding complications. However, the incidence of minor bleeding was higher in the warfarin group than the aspirin group. (J Cardiovasc Electrophysiol, Vol. 21, pp. 501‐507, May 2010)