NGMSElect™ and Investigator(®) Argus X-12 analysis in population samples from Albania, Iraq, Lithuania, Slovenia, and Turkey.

The analysis of STRs is the main tool when studying genetic diversity in populations or when addressing individual identification in forensic casework. Population data are needed to establish reference databases that can be used in the forensic context. To that end, this work investigated five population samples from Albania, Iraq, Lithuania, Slovenia, and Turkey. Individuals were typed for 16 autosomal STRs and 12 X-chromosomal STRs using the NGMSElect™ and Investigator(®) Argus X-12 kits, respectively. The aim of the study was to characterize the diversity of both STR kits in these population samples and to expand our forensic database. The results showed that all markers were polymorphic in the five populations studied. No haplotype was shared between the males analysed for X-STRs. No statistically significant deviations from Hardy-Weinberg equilibrium were observed for any of the genetic markers included in both the kits. Pairwise LD was only detected in X-STRs between markers located in the same linkage group. Power of discrimination values for males and females and the probability of exclusion in duos and trios were high for the populations in this study.

RNA/DNA co-analysis from human skin and contact traces--results of a sixth collaborative EDNAP exercise.

The European DNA profiling group (EDNAP) organized a sixth collaborative exercise on RNA/DNA co-analysis for body fluid/tissue identification and STR profiling. The task was to identify skin samples/contact traces using specific RNA biomarkers and test three housekeeping genes for their suitability as reference genes. Eight stains, a skin RNA dilution series and, optionally, bona fide or mock casework samples of human or non-human origin were analyzed by 22 participating laboratories using RNA extraction or RNA/DNA co-extraction methods. Two sets of previously described skin-specific markers were used: skin1 pentaplex (LCE1C, LCE1D, LCE2D, IL1F7 and CCL27) and skin2 triplex (LOR, KRT9 and CDSN) in conjunction with a housekeeping gene, HKG, triplex (B2M, UBC and UCE). The laboratories used different chemistries and instrumentation. All laboratories were able to successfully isolate and detect mRNA in contact traces (e.g., human skin, palm-, hand- and fingerprints, clothing, car interiors, computer accessories and electronic devices). The simultaneous extraction of RNA and DNA provides an opportunity for positive identification of the tissue source of origin by mRNA profiling as well as a simultaneous identification of the body fluid donor by STR profiling. The skin markers LCE1C and LOR and the housekeeping gene marker B2M were detected in the majority of contact traces. Detection of the other markers was inconsistent, possibly due to the low amounts and/or poor quality of the genetic material present in shed skin cells. The results of this and the previous collaborative RNA exercises support RNA profiling as a reliable body fluid/tissue identification method that can easily be combined with current STR typing technology.

The influence of pacing rate and autonomic blockade on human primary and secondary atrial pacemakers.

The morphology of the first spontaneous post-pacing P wave was assessed in 106 patients who underwent electrophysiological study for various arrhythmias. An overall number of 589 atrial pacing sessions, from 60-200 b/min, were analyzed (mean 5.55 +/- 1.3 session per patient). After cessation of 138 (23.42%) of them, spontaneous post-pacing P wave arose from extrasinus foci. Nonsinus spontaneous post-pacing P waves were recorded after 1 or more pacing rates (from 1 to 7) in 58 patients (54.7%, Group 1). In the remaining 48 patients the spontaneous post-pacing P waves were sinus after all pacing sessions (45.3%, Group 2). Sinus node disease (SND) was present in 32.7% of Group 1 patients and in 2% of Group 2 (p = 0.002). Spontaneous post-pacing P wave of extrasinus origin was recorded in 19/20 of SND patients (95%) compared to 39/86 of patients with normal sinus function (45.34%, p < 0.001). SND patients had a greater number of pacing sessions resulting in nonsinus spontaneous post-pacing P waves. Pacing rate associated with nonsinus spontaneous post-pacing P waves was lower in SND patients compared to patients with normal sinus node function. In the SND group, nonsinus spontaneous post-pacing P waves were recorded beyond the first spontaneous one in 9 patients compared to only 1 in patients with normal sinus node function (p < 0.005). Extrasinusal first spontaneous post-pacing P waves at a pacing rate of 140 b/min had the highest sensitivity (75%). Increasing of pacing rate from 60 to 140 b/min was associated with progressive arousal of secondary foci with highest value of 36.8% in pacing rate of 140 b/min. Further increase of pacing rate resulted in a slight reduction of spontaneous post-pacing firing from secondary foci. Atropine was administered in 12 Group 1 patients and abolished all measurable morphological changes of spontaneous post-pacing P waves compared to pre-pacing. Autonomic blockade was performed in 14 Group 1 patients and 16 Group 2 patients. In 35.7% of Group 1 patients autonomic blockade abolished the appearance of nonsinus spontaneous post-pacing P waves, while in the remaining patients increased the lowest pacing rate resulting in nonsinus spontaneous post-pacing P waves. In 12.5% Group 2 patients autonomic blockade resulted in nonsinus spontaneous post-pacing P waves after cessation of atrial pacing. In conclusion, the extrasinus spontaneous rise of atrial impulse is a very frequent phenomenon after atrial pacing especially in patients with SND. Pacing rate has different quantitative effects on sinus and secondary atrial pacemakers. Secondary pacemakers are less under autonomic control compared to sinus node.

[Complete vagal block in the clinical evaluation of sinus bradycardia]. / Le blocage vagal complet dans l'évaluation clinique de la bradycardie sinusale.

The authors determined the discriminant threshold of sinus rate (SR) and the degree of its increase after complete vagal block (0.04 mg/kg of atropine sulfate IV) in 34 patients with symptomatic sinus bradycardia, the day after electrophysiological evaluation (performed before and after autonomic block with propranolol 0.2 mg/kg and atropine sulfate 0.04 mg/kg IV). Patients were divided into two groups. Group I included 19 patients (age 43.3 +/- 8) with normal intrinsic sinus automatism with normal intrinsic heart rate (IHRo) and normal intrinsic corrected sinus recovery time (intrinsic CSRT) (< 425 ms). Group II consisted of 15 patients (age 51.8 +/- 12) with abnormal intrinsic sinus automatism with abnormal IHRo and/or intrinsic CSRT (> 425 ms). Following the atropine test, SR in the individuals of Group I increased from 58.1 +/- 11.7 bpm to 103 +/- 16 bpm (delta% = 80 +/- 37), while in Group II it increased from 52.8 +/- 12 bpm to 82.15 bpm (delta% = 55.4 +/- 21). The discriminant threshold of SR and of its percentage increase (delta%) were 91 bpm and 68% respectively, with a sensitivity of 71 and 81% and a specificity of 73 and 63%. The predictive value of a positive test of SR (< 91 bpm) and of its delta% (< 68%) were 71 and 64% respectively. That of a negative test of SR (> 91 bpm) and of its delta% (< 68%) were 73 and 80% respectively. The total predictive accuracy of SR and of its percentage increase was the same: 72%.(ABSTRACT TRUNCATED AT 250 WORDS)

The diagnostic significance of real sinus node automaticity depression in symptomatic sinus bradycardia.

Atrial overdrive pacing was performed, before and after autonomic blockade, in 42 consecutive patients (32 males and 10 females, mean age 46 +/- 11 years) with symptomatic sinus bradycardia. Patients were divided into two groups: Group I, 23 patients (mean age 43 +/- 8 years) with normal intrinsic heart rate (IHR) and normal intrinsic corrected sinus node recovery time (intrinsic CSNRT < 425 ms) and Group II, 19 patients (mean age 49 +/- 13 years) with abnormal intrinsic sinus node automaticity identified after autonomic blockade by abnormal IHR and/or by abnormal intrinsic CSNRT (> 425 ms). In addition to sinus cycle length, IHR, maximal CSNRT and sinoatrial conduction time (SACT) the real sinus node automaticity depression (SAD) was also evaluated, calculated after autonomic blockade (intrinsic CSNRT-SACT). Not all patients with an abnormal IHR showed abnormally prolonged CSNRT and not all patients with normal IHR had normal CSNRT. Among Group I (normal IHR) in 19 patients the real SAD was < 300 ms, while among Group II in 8 of 11 patients showing abnormal IHR the real SAD was > 300 ms. The abnormal value of SAD (> 300 ms) observed not only in patients with abnormal IHR and/or abnormally prolonged intrinsic CSNRT but also in several patients with normal IHR, increases the sensitivity of testing and may allow to detect even latent organic sinus node dysfunction. In conclusion, a synopsis of IHR, intrinsic CSNRT and intrinsic SACT with real SAD may be useful to estimate more accurately the degree of the impairment of intrinsic sinus node automaticity helping to differentiate the organic sinus node dysfunction from the autonomic one.

Comparative evaluation of verapamil, flecainide and propafenone for the acute conversion of atrial fibrillation to sinus rhythm.

In 69 consecutive patients with recent-onset atrial fibrillation, we compared the usefulness of verapamil, flecainide and propafenone for the acute conversion to sinus rhythm within 1 hour of the start of intravenous infusion. The patients were randomized to receive verapamil, 10 mg in 5 minutes (n = 29), flecainide, 2 mg/kg in 10 minutes (n = 20) or propafenone, 2 mg/kg in 10 minutes (n = 20). The 3 treatment groups did not differ significantly regarding patient baseline characteristics. Conversion rate was 14% for verapamil, 50% for flecainide and 25% for propafenone. A significant difference (p = 0.02) was found only between the verapamil and flecainide results. Mean time to conversion did not differ significantly. Stepwise multiple regression analysis revealed that the only variables correlating with the final result were the type of treatment (p = 0.001) and the duration of arrhythmia (p = 0.005). Mean duration of arrhythmia in converted patients was significantly shorter than in non-converted patients (9.7 [6.6] vs 34.0 [46.1] hours, p = 0.03). Serious side effects were seen only during propafenone infusion (2 patients developed severe hypotension necessitating discontinuation of therapy and administration of intravenous fluids). We conclude that intravenous flecainide appears to be more effective than the other 2 drugs for the acute conversion of recent-onset atrial fibrillation to sinus rhythm.