Renal artery aneurysm as a cause of resistant hypertension in a young female--case report

A case of a 19-year-old woman suffering for 5 years from pharmacologically resistant hypertension, is presented. During invasive diagnostic procedures left renal artery aneurysm was found. Surgical resection with vessel prosthesis implantation was successfully performed. Examination carried-out 6 months later revealed good response to pharmacological treatment with normal levels of blood pressure.     

Dynamics of Ventricular Repolarization in Patients with Dilated Cardiomyopathy Versus Healthy Subjects

Background: Patients with impaired left ventricular function have a high risk of developing ventricular arrhythmias and sudden death. Among different markers of risk, the prolongation and regional heterogeneity of repolarization are of increasing interest. However, there are limited data regarding feasibility of analyzing repolarization parameters and their dynamics in 24‐hour Holter ECG recordings. Methods: Dynamic behavior of repolarization parameters was studied with a new automatic algorithm in digital 24‐hour Holter recordings of 60 healthy subjects and 55 patients with idiopathic dilated cardiomyopathy (IDC). Repolarization parameters included the mean value of QT and QTc durations, QT dispersion, and peaks of QT duration and QT dispersion above prespecified thresholds. Results: In comparison to healthy subjects, patients with IDC had lower heart rate variability, longer mean QT and QTc durations, higher content of QTc peaks >500 ms, longer QT dispersion and its standard deviation, and a higher content of peaks >100 ms of QT dispersion (P < 0.01 for all comparisons). These repolarization parameters were significantly higher in IDC patients after adjustment for age, sex, and heart rate variability. The parameters of repolarization dynamics correlated with SDNN in healthy subjects but not in dilated cardiomyopathy patients. Conclusions: The automatic assessment of repolarization parameters in 24‐hour digital ECG recordings is feasible and differentiates dilated cardiomyopathy patients from healthy subjects. Patients with dilated cardiomyopathy have increased QT duration, QT dispersion, and increased variability of QT dispersion reflecting variations in T‐wave morphology, the factors which might predispose them to the development of arrhythmic events.     

First heart sound and opening snap in patients with mitral valve disease. Phonocardiographic and pathomorphologic study

Patients with exercise angina >2 months (n:13) showed significantly lower SigmaST elevation during 120 s balloon coronary occlusion than those with =<2 months (n:7), or those with angina at rest <=2 days (n:8) but similar to patients with angina at rest >2 days (n:7). These results underscore the importance of the kind and duration of angina in limiting the extent of ischemia during coronary occlusion.     

Serum glucose and triglyceride determine high-risk subgroups in non-diabetic postinfarction patients

A strategy was developed to identify subgroups at high risk for recurrent coronary events in non-diabetic postinfarction patients as a function of metabolic, inflammatory, and thrombogenic blood markers. A graphical screening technique for presumptively identifying high-risk subgroups from outcome prevalence maps was devised that was equally sensitive for all values of risk factors in contrast to traditional approaches where risk is presumed for the highest or the lowest values. Traditional statistical analysis confirms high risk in identified subgroups. Serum glucose and triglyceride served as bivariate search domain. Results demonstrated three high-risk subgroups. One was characterized as pre-diabetic; another as metabolic syndrome-enriched; and the third, with unexpectedly high risk, as normoglycemic and modestly hypertriglyceridemic. Within-subgroup risk as determined by Cox proportional hazards model gave for odds ratios and 95 percentile confidence intervals: glucose, 2.49 (1.17-5.33) in pre-diabetic; PAI-1, 3.95 (1.81-8.61) in metabolic syndrome-enriched; and BMI, 2.79 (1.17-6.63) and fibrinogen, 2.79 (1.29-6.04) in normoglycemic, modestly hypertriglyceridemic patients. We conclude that the graphical approach holds promise in screening for high-risk patient subgroups. Finding different within-subgroup predictors of risk underscores the notion of context-dependent risk, an observation that may be relevant for determining optimal use of emerging risk factors.     

Pharmacological versus invasive treatment in patients with atrial fibrillation

Aim of this prospective study was to assess quality of life (QoL), left ventricular (LV) function and exercise performance in two groups of patients (pts) with atrial fibrillation (Af) treated with: radiofrequency catheter ablation (RFA) and antiarrhythmic drugs (AA). Between 1996 and 2000 - 74 patients, 28 women, with drug refractory Af were enrolled by clinical indications for two modes of therapy: RFA and AA. RFA group consisted of 38 pts, 63.7 +/- 11.5 years old: 28 pts with RF AV Node ablation and pacemaker implantation (PI) and 10 pts with AV Node modification or right atrial isthmus RF ablation due to Af conversion to atrial flutter (Aflu) during medical therapy. AA group consisted of 36 pts, aged 59.7 +/- 13.8 years. Patients from RFA group suffered significantly more serious diseases than pts from AA group. No significant (sign.) differences between two groups were found in age, gender, arrhythmia history and number of AA taken. Pts were analyzed before entry, after 3 and 12 months of follow-up (3 mo. FU, 12 mo. FU) with following indices: LV function (Echo: EF & FS), exercise performance (treadmill test), QoL questionnaires, number of hospital admissions connected to arrhythmia or procedures (RFA & PI), number of AA drugs taken in RFA group. RFA group: Two deaths occurred due to end stage respiratory insufficiency (COPD), one pt required reposition of pacemaker lead. AA group: 3 pts required RFA due to uncontrolled Af/Aflu (AV Node ablation with PI - 1 pt, right atrial isthmus ablation - 2 pts). Analysis of two patients groups: LV function: Sign. improvement (EF & FS) in both groups in 12 mo. FU; Exercise performance: no sign. changes in 3 and 12 mo. FU. QoL: Arrhythmia scale: 3 mo. FU sign. reduction in both groups; 12 mo. FU reduction in RFA group only; Anxiety scale: 3 and 12 mo. FU sign. reduction of anxiety level in RFA group; Exercise and activity scales: 3 and 12 mo. FU sign. improvement in RFA group. During 3 and 12 mo. FU sign. less pts from RFA group required hospital admission versus pts from AA group. Sign. reduction in AA was noted in RFA group. Patients with symptomatic Af treated with RFA benefit from this kind of therapy more than patients treated with AA. Quality of life improvement visible in short term observation in patients from RFA group is still present after one year observation. Improvement in LV function is observed after one year in both groups of pts with Af.     

Improvement in Solubility and Molecular Assembly of Cyclopentadithiophene–Benzothiadiazole Polymer

Using linear side chains for conjugated polymers is hindered by their limited solubility in common organic solvents, creating problems during purification and processing, whereas branched alkyl chains generally preclude interchain interdigitation because their bulkiness usually hinders interchain interactions. To compensate the adverse effects from each side chain, it is shown that replacing commonly employed 2‐ethylhexyl (2EH) solubilizing groups with branched 5‐ethylnonyl (5EN) chains not only improves solution processability to PCDT‐BT polymer, but also induces an advantageous change in polymer self‐assembly and backbone orientation in thin films that correlates with an increase in transistor performance.

     

Mid-infrared spectroscopy and microscopy of subcellular structures in eukaryotic cells with atomic force microscopy – infrared spectroscopy

Atomic force microscopy – infrared (AFM-IR) spectroscopy allows spectroscopic studies in the mid-infrared (mid-IR) spectral region with a spatial resolution better than is allowed by the diffraction limit. We show that the high spatial resolution can be used to perform spectroscopic and imaging studies at the subcellular level in fixed eukaryotic cells. We collect AFM-IR images of subcellular structures that include lipid droplets, vesicles and cytoskeletal filaments, by relying on the intrinsic contrast from IR light absorption. We also obtain AFM-IR absorption spectra of individual subcellular structures. Most spectra show features that are recognizable in the IR absorption spectra of cells and tissue obtained with FTIR technology, including absorption bands characteristic of phospholipids and polypeptides. The quality of the spectra and of the images opens the way to structure and composition studies at the subcellular level using mid-IR absorption spectroscopy.

Atomic force microscopy – infrared (AFM-IR) spectroscopy allows spectroscopic studies in the mid-infrared (mid-IR) spectral region with a spatial resolution better than is allowed by the diffraction limit.     

Electrochemical and optoelectronic properties of terthiophene- and bithiophene-based polybenzofulvene derivatives

The electrochemical behavior of some polybenzofulvene derivatives bearing bithiophene (BT) or terthiophene (TT) side chains was investigated by cyclic voltammetry. Very interestingly, the presence of unsubstituted terminal thiophene moieties allowed poly-6-BT-BF3k and poly-6-TT-BF3k to be cross-linked by electrochemical procedures. Conductive films were obtained by electrodeposition from solutions of these polymers onto electrode surfaces through the formation of covalent cross-linking due to dimerization (i.e. electrochemical oxidation) of the BT or TT side chains. The films showed electrochromic features and switched from yellow-orange (neutral) to green (positively charged) by switching the potential, and were stable to tenths of cycles, without degradation in the wet state in the electrolyte solution. Finally, the thin film obtained by electrodeposition of poly-6-TT-BF3k on a indium tin oxide (ITO) glass substrate showed in the neutral state a significantly red-shifted photoluminescence (PL) emission (∼40 nm red-shifted with respect to that of the corresponding film obtained by casting procedures), which was consistent with the presence of more conjugated moieties produced by the oxidative dimerization of the TT side chains. The innovative architecture and the easy preparation could lead to a broad range of applications in optoelectronics and bioelectronics for these cross-linked hybrid materials based on π-stacked polybenzofulvene backbones bearing oligothiophene side chains.

The electrochemical behavior of some polybenzofulvene derivatives bearing bithiophene (BT) or terthiophene (TT) side chains was investigated by cyclic voltammetry and cross-linked materials were obtained by dimerization of the BT or TT side chains.     

Oral Prolonged‐Release Oxycodone/Naloxone for Managing Pain and Opioid‐Induced Constipation: A Review of the Evidence

Background

Opioids provide effective relief from moderate‐to‐severe pain and should be prescribed as part of a multifaceted approach to pain management when other treatments have failed. Fixed‐dose oxycodone/naloxone prolonged‐release tablets (OXN PR) were designed to address the opioid class effect of opioid‐induced constipation (OIC) by combining the analgesic efficacy of oxycodone with the opioid receptor antagonist, naloxone, which has negligible systemic availability when administered orally. This formulation has abuse‐deterrent properties, since systemic exposure to naloxone by parenteral administration would antagonize the euphoric effects of oxycodone.

Methods

A literature search was conducted to assess the evidence base for OXN PR to treat moderate‐to‐severe pain and its impact on bowel function, based on published clinical trials and observational studies.

Results

Extensive data demonstrate that OXN PR provides effective analgesia and clinically relevant improvements in bowel function in patients with OIC and moderate‐to‐severe cancer‐related pain and noncancer pain types such as low back pain, neuropathic pain, and musculoskeletal pain. OXN PR has also been found to improve bowel function in patients with OIC refractory to multiple types of laxatives, and improve Parkinson's disease–related pain. No unanticipated safety concerns have been reported in elderly patients.

Conclusions

Evidence from clinical trials and observational studies confirms that for selected patients OXN PR significantly improves moderate‐to‐severe chronic pain and provides relief from OIC. Treatment should be tailored to individual patients to establish the lowest effective dose. An absence of analgesic ceiling effect was seen across the clinically relevant dose range investigated (≤ 160/80 mg/day).     

The influence of substituent field and resonance effects on the ease of N-heterocyclic carbene formation from imidazolium rings

Using a set of twelve selected substituents, the influence of substituent properties on the ease of deprotonation of imidazolium cations and mesoionic imidazolium-4-olates measured by the CREF index has been investigated. Significant correlations between CREF values and the Swain and Lupton field (F) and resonance (R) substituent constants have been found. In all cases the field effect has the greatest influence but resonance effects are also significant.

The influence of substituents on the relative acidity of C–H bonds.