Comparison of methods of DNA extraction for real‐time PCR in a model of pleural tuberculosis

Santos A, Cremades R, Rodríguez JC, García‐Pachón E, Ruiz M, Royo G. Comparison of methods of DNA extraction for real‐time PCR in a model of pleural tuberculosis. APMIS 2010; 118: 60–5. Molecular methods have been reported to have different sensitivities in the diagnosis of pleural tuberculosis and this may in part be caused by the use of different methods of DNA extraction. Our study compares nine DNA extraction systems in an experimental model of pleural tuberculosis. An inoculum of Mycobacterium tuberculosis was added to 23 pleural liquid samples with different characteristics. DNA was subsequently extracted using nine different methods (seven manual and two automatic) for analysis with real‐time PCR. Only two methods were able to detect the presence of M. tuberculosis DNA in all the samples: extraction using columns (Qiagen) and automated extraction with the TNAI system (Roche). The automatic method is more expensive, but requires less time. Almost all the false negatives were because of the difficulty involved in extracting M. tuberculosis DNA, as in general, all the methods studied are capable of eliminating inhibitory substances that block the amplification reaction. The method of M. tuberculosis DNA extraction used affects the results of the diagnosis of pleural tuberculosis by molecular methods. DNA extraction systems that have been shown to be effective in pleural liquid should be used.     

A Fast and Reliable Algorithm to Localize Accessory Pathways Based on the Polarity of the QRS Complex on the Surface ECG During Sinus Rhythm

d 'AVILA, A., et al .: A Fast and Reliable Algorithm to Localize Accessory Pathways Based on the Polarity of the QRS Complex on the Surface ECG During Sinus Rhythm . Background: Many criteria have been published to localize accessory pathways from the 12-lead EGG during sinus rhythm. This study analyzed whether the localization of an accessory pathway could be predicted by using the polarity of the QRS complex during sinus rhythm on the surface ECG, instead of the delta wave polarity as used in many reports. Methods: The ECGs of 140 patients with an overt and single accessory pathway were evaluated. Eight localizations were taken into account. The precise location was previously known from successful radiofrequency ablation sites. Results: In 128 patients (92%), the new algorithm allowed an accurate diagnosis of the site of implantation of the accessory pathway. Conclusion: Analysis of the polarity of the QRS complex on five electrocardiographic leads provides an easy, fast and reliable way to localize accessory pathways during sinus rhythm.     

Age-related changes in rat cerebellar basket cells: a quantitative study using unbiased stereological methods

Cortical cerebellar basket cells are stable postmitotic cells; hence, they are liable to endure age‐related changes. Since the cerebellum is a vital organ for the postural control, equilibrium and motor coordination, we aimed to determine the quantitative morphological changes in those interneurons with the ageing process, using unbiased techniques. Material from the cerebellar cortex (Crus I and Crus II) was collected from female rats aged 2, 6, 9, 12, 15, 18, 21 and 24 mo (5 animals per each age group), fixed by intracardiac perfusion, and processed for transmission electron microscopy, using conventional techniques. Serial semithin sections were obtained (5 blocks from each rat), enabling the determination of the number‐weighted mean nuclear volume (by the nucleator method). On ultrathin sections, 25 cell profiles from each animal were photographed. The volume density of the nucleus, ground substance, mitochondria, Golgi apparatus (Golgi) and dense bodies (DB), and the mean surface density of the rough endoplasmic reticulum (RER) were determined, by point counting, using a morphometric grid. The mean total volumes of the soma and organelles and the mean total surface area of the RER [s?_N (RER)] were then calculated. The results were analysed with 1‐way ANOVA; posthoc pairwise comparisons of group means were performed using the Newman‐Keuls test. The relation between age and each of the parameters was studied by regression analysis. Significant age‐related changes were observed for the mean volumes of the soma, ground substance, Golgi, DB, and s?_N (RER). Positive linear trends were found for the mean volumes of the ground substance, Golgi, and DB; a negative linear trend was found for the s?_N (RER). These results indicate that rat cerebellar basket cells endure important age‐related changes. The significant decrease in the s?_N (RER) may be responsible for a reduction in the rate of protein synthesis. Additionally, it may be implicated in a cascade of events leading to cell damage due to the excitotoxic activity of glutamate, which could interfere in the functioning of the complex cerebellar neuronal network.     

Complications and Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement With Edwards SAPIEN & SAPIEN XT Valves: A Meta‐Analysis of World‐Wide Studies and Registries Comparing the Transapical and Transfemoral Accesses

Introduction

Both transfemoral (TF) and transapical (TA) routes are utilized for Transcatheter Aortic Valve Replacement (TAVR) using Edwards SAPIEN & SAPIEN XT valves. We intended to perform a meta‐analysis comparing the complication rates between these two approaches in studies published before and after the standardized Valve Academic Research Consortium (VARC) definitions.

Methods

We performed a comprehensive electronic database search for studies published until January 2014 comparing TF and TA approaches using the Edwards SAPIEN/SAPIEN XT aortic valve. Studies were analyzed based on the following endpoints: 1‐year mortality, 30‐day mortality, stroke, new pacemaker implantation, bleeding, and acute kidney injury.

Results

Seventeen studies were included in the meta‐analysis. Patients undergoing TA TAVR had a significantly higher logistic EuroSCORE (24.6 ± 12.9 vs. 21.3 ± 12.0; P < 0.001). The cumulative risks for 30‐day mortality (RR 0.61; 95%CI 0.46–0.81; P = 0.001), 1‐year mortality (RR 0.68; 95%CI 0.55–0.84; P < 0.001), and acute kidney injury (RR 0.53; 95%CI 0.38–0.73; P < 0.001) were significantly lower for patients undergoing TF as compared to TA approach. Both approaches had a similar incidence of 30‐day stroke, pacemaker implantation, and major or life‐threatening bleeding. Studies utilizing the VARC definitions and those pre‐dating VARC yielded similar results.

Conclusion

This meta‐analysis demonstrates a decreased 30‐day and 1‐year mortality in TF TAVR as compared to TA TAVR. Post‐procedure acute kidney injury and the need for renal replacement therapy are also significantly lower in the TF group. These differences hold true even after utilizing the standardized Valve Academic Research Consortium criteria. (J Interven Cardiol 2015;28:266–278)

     

Clinical and Electrophysiologic Features of Syncope in Chronic Chagasic Heart Disease

Syncope in CCHD. Introduction: Syncope in patients with chronic Chagasic heart disease (CCHD) is a frequent hut poorly studied problem.
Methods and Results: Fifty-three patients with CCHD and recurrent syncope were followed for 2 to 127 months. They were classified into the following groups: G-I (n = 15) without inducible ventricular tachycardia (VT) and normal HV interval; G-II (n = 17) with only inducible VT; G-III (n = 11) with only an abnormal HV interval; and G-IV (n = 10) with both an inducible VT and an abnormal HV interval. Empiric pharmacologic therapy was given in G-I; pharmacologic therapy guided by electrophysiologic: study in G-II; atrioventricular pacing in G-III; and empiric pharmacologic with atrioventricular pacing in G-IV. Age and sex were similar among groups; New York Heart Association Functional Class I symptoms were more prevalent (P = 0.0001) in G-I. The ejection fraction by echocardiography was higher in G-I (P = 0.01221. The density of premature ventricular complexes by Duller monitoring was similar among groups. The complexity of premature ventricular complexes by Holler was significantly higher in G-II (P = 0.0270); this variable, analyzed from the exercise electrocardiogram, was not different among groups. All deaths were sudden, prevalence was higher in G-II and absent in G-III, and recurrence of syncope was similar among groups.
Conclusion: The most probable causes of recurrent syncope were VT (43%) with poor prognosis, and paroxysmal atrioventricular block (21%) with a favorable prognosis. Absence of congestive heart failure, complexity of premature ventricular complexes by Holler, and absence of intraventricular heart block showed statistical correlation with normal electrophysiologic study, inducible VT, and normal HV interval, respectively.     

Selective Vagal Denervation of the Sinus and Atrioventricular Nodes, Guided by Vagal Reflexes Induced by High Frequency Stimulation, to Treat Refractory Neurally Mediated Syncope

A 15-year-old female patient presented with frequent episodes of vasovagal syncope refractory to non-pharmacological and pharmacological measures. Two tilt-table tests performed before and after conventional therapy were positive and reproduced the patient's clinical symptoms. Selective vagal denervation, guided by HFS, was performed. Six radiofrequency pulses were applied on the left and right sides of the interatrial septum, abolishing vagal responses at these locations. Basal sinus node and Wenckebach cycle lengths changed significantly following ablation. A tilt test performed after denervation was negative and revealed autonomic tone modification. The patient reported significant improvement in quality of life and remained asymptomatic for 9 months after denervation. After this period, three episodes of NMS occurred during a 4-month interval and a tilt test performed 11 months after the procedure demonstrated vagal activity recovery.     

The Long-Term Host Response to Liquid Silicone Injected during Soft Tissue Augmentation Procedures: A Microscopic Appraisal

BACKGROUND Silicone has a long history of use as a soft tissue filler.
MATERIALS AND METHODS As a contribution to the clarification of the role and fate of this material when used as a filler in soft tissue augmentation techniques, 35 skin biopsies were examined by light microscopy. These biopsies were obtained from target areas where liquid silicone had been injected in 25 patients between 1 and 23 years prior, for the correction of depressed scars on the face.
RESULTS The microscopic study revealed in 100% of the cases the continued presence, in significant amounts, of the silicone previously injected into the target areas, where it failed to elicit any significant adverse reaction.
CONCLUSION Owing to its high permanence and to its inertness, reflected by the lack of any adverse reaction to its presence in the target site, silicone should be regarded as a valuable filler, at least for the correction of small depressed facial scars.