Reproducibility of Two Four-Point Clinical Severity Scores for Lateral Canthal Lines (Crow''s Feet)

BACKGROUND: Several clinical scoring systems have been used to evaluate the efficacy of botulinum toxin A in the treatment of hyperkinetic wrinkles. So far very few have been investigated for their reproducibility. OBJECTIVE: The aim of this study was to investigate the reproducibility of two clinical four-point scales for lateral canthal lines (crow's feet), at rest and at maximum smile. MATERIAL AND METHODS: Based on standardized photographs, a consensus atlas depicting the different severity grades [from 0 (none) to 3 (severe)] was developed. After training based on the atlas, 49 photographs at rest and 48 at maximum smile were graded by the same group of investigators on 2 consecutive days (n=9 on Day 1; n=8 on Day 2). The scores were compared for reproducibility using kappa statistics. RESULTS: Overall, reproducibility was good for both scales. Interobserver reproducibility showed an agreement of 0.6 at rest and 0.58 at maximum smile (unweighted kappa). Intraobserver reproducibility showed an agreement between 0.47 and 0.86 at rest and between 0.62 and 0.81 at maximum smile (unweighted kappa). Using weighted kappa analysis, the agreement ranged between 0.63 and 0.91 at rest and between 0.71 and 0.85 at maximum smile. CONCLUSION: The clinical scales using scores of 0 to 3 for crow's feet, both at rest and at maximum smile, show a good inter- and intraobserver reproducibility. The use of these scores in clinical trials can be recommended.     

Arrhythmogenic Effects of Quinidine on Catecholamine-Induced Delayed Afterdepolarizations in Canine Atrial Fibers

Arrhythmogenic Effects of Quinidine on Catecholamine-induced Delayed Afterdepolarizations. We studied the effects of quinidine and tetrodotoxin (TTX), two drugs that block Na⁺ channels, on delayed afterdepolarizations (DAD) caused by norepinepbrine in atrial fibers of the canine coronary sinus. At long stimulus cycle lengths of 10 seconds, quinidine increased the amplitude of the afterdepolarizations and caused triggered activity within 1–2 minutes. Simultaneously, action potential duration (APD) was lengthened but upstroke velocity was not decreased. Prolonged exposure to quinidine eventually decreased upstroke velocity but DAD amplitude remained larger than control and triggered activity was still induced more easily. The effects of quinidine to increase afterdepolarizations was partially related to its prolongation of the APD since shortening APD with repolarizing current decreased DAD amplitude. However, DAD amplitude remained larger than control indicating that quinidine caused triggering by other mechanisms as well. TTX, on the other hand, which blocks Na⁺ channels but shortens APD, decreased DAD amplitude and triggered activity. Part but not all of these effects resulted from the shortening of APD by TTX since prolongation of APD with depolarizing current only partially restored DAD amplitude. Anti-arrhythmic drugs, therefore, may have effects on DADs that partly result from changes in the APD. Quinidine may cause cardiac arrhythmias by virtue of its effects to potentiate triggered activity.     

Fat Content and Fatty Acid Composition of Infant Formulas

ABSTRACT. Fat content and fatty acid composition of 25 commercial infant formulas sold in the Federal Republic of Germany and of 3 home-made milk formulas were analysed, using gravimetry of extracted lipids and high-resolution capillary gaschromatography. Results were compared with the composition of human milk. Fat contents of all commercial formulas were similar to human milk values and met current recommendations, but 2 home-made preparations were at the upper and lower limits of the recommended range. Milk formulas tended to contain higher percentages of saturated and lower ones of cis-monounsaturated and trans-isomeric fatty acids than human milk. Linoleic acid (C18:2n-6) content was similar to human milk in most products but deviated clearly from recommended values in 2 home-made mixtures. Alpha-linolenic acid (C18:3n-3) values were often low in formulas, resulting a high n-6/n-3-ratios. In contrast to human milk, all formulas contained only minor amounts of the physiologically important long-chain polyunsaturated fatty acids with 20 and 22 carbon atoms. Some seasonal variation in the content of palmitic (C16:0), oleic (C18:ln-9), linoleic and trans-fatty acids was found when five arbitrarily selected adapted formulas were analysed repeatedly over one year. The composition of a home-made formula made from fresh cow's milk was markedly different in winter and in summer, when percentages of saturated and trans-fatty acids were higher and of linoleic acid were lower. We conclude that the composition of most commercial formulas is better suited to meet the lipid requirements of young infants than the home-made preparations investigated. However, the essential fatty acid composition of available milk formulas differs from that of human milk.     

Cerebral metabolism during deep hypothermic circulatory arrest vs moderate hypothermic selective cerebral perfusion in a piglet model: a microdialysis study

Background: Few data exist regarding antegrade selective cerebral perfusion (ASCP) and its application in newborn and juvenile patients. Clinical data suggest ASCP alone to be superior to deep hypothermic circulatory arrest (DHCA); however, the effects of moderate hypothermia during ASCP on cerebral metabolism in this patient population are still unclear. Methods: After obtaining the approval from animal investigation committee, 16 piglets were randomly assigned to circulatory arrest combined with either ASCP at 27°C or DHCA at 18°C for 90 min. Cerebral oxygen extraction fraction (COEF) from blood as well as cerebral tissue glucose, glycerol, lactate, pyruvate, and the lactate/pyruvate ratio (L/P ratio) by microdialysis were obtained repeatedly. Results: COEF was lower during cooling and rewarming, respectively, in the DHCA18 group compared to the ASCP27 group (30 ± 8 vs 56 ± 13% and 35 ± 6 vs 58 ± 7%, respectively). Glucose decreased in both the DHCA18 and ASCP27 groups during the course of cardiopulmonary bypass (CPB), but were higher in the ASCP27 group during ASCP, compared to the DHCA18 group during circulatory arrest (0.7 ± 0.1 vs 0.2 ± 0.1 mm ·l^?1, P < 0.05). Pyruvate was higher (ASCP27 vs DHCA18: 53 ± 17 vs 6 ± 2 μm ·l^?1, P < 0.05), and the L/P ratio increased during circulatory arrest in the DHCA18 group, compared to the selective perfusion phase of the ASCP27 group (DHCA18 vs ASCP27: 1891 ± 1020 vs 70 ± 28, P < 0.01). Conclusions: In this piglet model, both cerebral oxygenation and microdialysis findings suggested a depletion of cerebral energy stores during circulatory arrest in the DHCA18 group, compared to selective cerebral perfusion combined with circulatory arrest in the ASCP27 group.     

Is Atrial Sensing of Ventricular Far-Field Signals Important in Single-Lead VDD Pacing?

In single-lead VDD pacing the atrial sensitivity frequently is programmed to sensitive values. Atrial sensing of ventricular far-field signals should be reduced by differential atrial sensing. The aim of the study was to evaluate the effectiveness of this approach. Methods: The study included 10 patients with a single-lead VDD pacemaker (Thera 8948, Lead 5032). The atrial sensitivity was set to its most sensitive value of 0.18 mV and the telemetered intraatrial EGM was continuously recorded. After atrial tracked ventricular pacing, VVI pacing was performed with pacing rates from 100 to 160 beats/min in steps of 10 beats/min and up to 165 beats/min. The peak-to-peak amplitudes of P waves (P) and ventricular far-field signals (VFFS) were measured from the recordings. The ratio P/VFFS that defines the atrial signal-to-noise ratio was calculated, and the time from stimulus to maximum of the far-field signals amplitude (Tmax) was measured. Results: P measured 0.98 ± 0.76 mV. A VFFS was visible in the atrial channel in all patients with an amplitude of 0.45 ± 0.25 mV (range 0.01–1.0 mV), independent of the pacing rate. The ratio P/VFFS was 3.9 ± 4.2 (range 0.9–21.0). Tmax measured 99.4 ± 15.2 ms during sinus rhythm. A rate dependent shortening of Tmax to 92.7 ± 11.2 ms at 140 beats/min was observed (P = 0.001). At rates above 140 beats/min no further shortening occurred. Conclusion: Ventricular far-field signals are measurable in the atrial channel of VDD systems and may reach considerable amplitudes, which are not rate dependent. Although differential sensing provides favorable P waves to ventricular far-field signal ratios, refractory periods are needed to avoid far-field sensing. The rate dependent shortening of the ventricular signal can be detected in the atrial channel in VDD pacing.