Colonoscopic Polypectomy

A total of 87 polyps were treated during 62 colonoscopic examinations on 60 patients; 69 polyps were resected and 18 were fulgurated with the hot-biopsy forceps. Fifteen patients were under 13 years old, and the average age was 38 years. Twelve patients had more than one polyp. There were no complications and the method could be carried out in all patients, whenever it was indicated. Sixteen polyps were hamartomas, 13 shistosomatic, six hyperplastic, two lymphoid and 36 adenomas. Among these adenomas, six showed evidence of foci carcinoma, one in situ and five, invasive. Surgical resection was indicated in only one patient with sessile polyp with invasive focus of carcinoma. No metastasis was detected whatsoever.     

Assessment of Clockwise Cavotricuspid Isthmus Block Based on Conduction Times during Transient Entrainment: A Prospective Study

Background: In typical counterclockwise atrial flutter (AFL), the route of impulse propagation to anteroinferior right atrium (AIRA) during transient entrainment (TE) from the coronary sinus (CS) is expected to be similar to that during pacing from the same CS site during sinus rhythm (SR) when cavotricuspid isthmus (CTI) block has occurred. This could be used to identify CTI block during ablation procedures.
Methods: Thirty-six patients with AFL (cycle length [CL], 240 ± 25 ms) underwent CTI ablation during AFL. CS pacing was performed at a CL of 20 ms less than AFL CL before ablation (n = 36), and at several CL during SR with conduction through the CTI (n = 21) and after CTI block (n = 36).
Results: TE with orthodromic activation of AIRA occurred in all 36 patients. Conduction time from CS to AIRA during TE (T-entr, 199 ± 29 ms) was significantly longer than during pacing in SR (T-CTI) at the same rate not only with CTI conduction (T-CTI-C, 135 ± 24 ms, P < 0.001), but also with CTI block (T-CTI-B, 186 ± 24 ms, P < 0.01). T-entr did not correlate with T-CTI-C, but there was an excellent correlation between T-entr and T-CTI-B (r = 0.874, P < 0.001). A "TE index" that corrected T-CTI for individual T-entr identified CTI block with 97% sensitivity and 91% specificity. T-CTI at low rates differed from T-CTI at high rates but correlated significantly with them.
Conclusion: Comparison of conduction times during TE from the CS and during pacing from the same site and rate in SR can help to establish whether clockwise CTI block has been achieved in patients with typical AFL.     

Transcoronary Chemical Ablation of Incessant Atrial Tachycardia

Transcoronary Ablation of Incessant Atrial Tachycardia. Incessant atrial tachycardia, of at least 10 years duration and not controllable by antiarrhythmic drugs, was ablated by means of transcoronary administration of ethanol in a 24–year-old female. The arrhythmia was suppressed completely without recurrences during 8 months of follow-up. (J Cardiovasc Electrophysiol, Vol. 1, pp. 116–120, 1990)     

Morphological and histochemical changes in the epididymis of hamsters (Mesocricetus auratus) subjected to short photoperiod

The morphological involution and histochemical changes of the Syrian hamster ( Mesocricetus auratus ) epididymis induced by a short light period were investigated. Under short-day conditions, the epididymis showed marked morphological changes including a decrease in luminal diameter, disappearance of spermatozoa, increase of interductal tissue, increase of intraepithelial lipofuscin deposits, the presence of phagolysosomes in the principal cells and macrophage-like cells, and a considerable modification of most clear cells. With lectin histochemistry changes were found in the glycoconjugates of principal cells of the regressed epididymis, either a decrease (PNA, WGA, HPA and DBA) or an increase (MAA) in the affinity of lectins to the Golgi area, or a decrease (HPA) or an increase (PNA) in lectin binding to stereocilia. Both morphological and histochemical results showed that, under this light condition, the cauda epididymidis presented the most prominent alterations, and that the epididymis showed increased absorptive activity and a decreased synthesis of glycoproteins. All these changes are probably due to the decrease in testosterone levels.     

Epidemiology of congenital pigmented naevi:

Genetic and environmental risk factors were investigated in a sample of 989 non-malformed newborn infants with skin pigmented naevi (PN), and in 989 non-malformed non-PN, control babies. The samples were obtained from a population of 531,831 livebirths, from fifty-nine South-American maternity hospitals. No significant differences were observed between the PN and control groups for the following risk factors: sex, twinning, parental consanguinity, socioeconomic level, parental ages, birth order, fetal presentation, type of delivery, postnatal mortality, and first trimester of pregnancy histories for maternal chronic illnesses or immunizations, radiation exposure, drug intake, and vaginal bleeding. PN infants were associated with high frequencies of Black racial ancestry, positive prenatal history for maternal acute illnesses, and high mean values for length of gestation and birth weight. The observed association of PN with maternal acute illnesses could be a spurious one, due to partial dependence upon Black racial ancestry, and to maternal memory bias. The analysis of the intrauterine growth curves showed that PN infants have a low prematurity rate, and a high mean birth weight within the postmature group, lacking the normal post-term weight loss pattern shown by the control newborn group. This observation suggests that congenital PN appear in the latest stages of intrauterine development. No evidence was obtained to allow us to consider congenital PN as true developmental anomalies.