A linkage between hereditary hyperferritinaemia not related to iron overload and autosomal dominant congenital cataract

Summary. The only genetic disorder with elevated serum ferritin levels so far described is hereditary HLA-related haemochromatosis. On the other hand, hereditary cataract is both genotypically as well as phenotypically heterogenous, and no specific locus or any useful marker has been yet identified. We studied two Italian families in whom a combination of elevated serum ferritin not related to iron overload and congenital nuclear cataract is transmitted as an autosomal dominant trait. Affected individuals have normal serum iron and transferrin saturation, but high serum ferritin. Red cell counts are normal and venesection therapy rapidly produces iron-deficiency anaemia.
This genetic disorder, which is characterized by hyperferritinaemia, differs from hereditary HLA-related haemochromatosis mostly for the absence of iron overload. A gene responsible for the congenital nuclear cataract likely maps on chromosome 19q close to the ferritin L-subunit gene. Within families with autosomal dominant congenital cataract, serum ferritin might be an early marker of disease.     

Platelet Aggregability in Patients with a VVI Pacemaker

Several studies have suggested an increased incidence of thromboembolic events in patients with VVI pacemaker (VVI patients); furthermore, other authors have demonstrated that a treatment with anticoagulants or antiplatelet drugs may be effective in reducing thromboembolic events, thus suggesting an increased formation of platelet thrombi in these patients. In this respect, platelet aggregability was investigated in ten VVI patients and ten age– and sex–matched subjects. β–thromboglobulin (β–Tg) and platelet factor 4 (PF4) plasma levels were determined as weJJ as platelet aggregation induced by ADP, collagen, epinephrine, and arachidonic acid. Plasma β–Tg JeveJs were increased in the patient group (86 ± 24 vs 24 ± 13 ng/mL; P < 0.001) in presence of normal PF4 values (14 ± 11 vs 13 ± 6 ng/mL; NS). Aggregation curves showed abnormal values of maximal amplitude, slope, and lag time. In particular, maximal amplitude was significantJy higher in VVI patients as compared with controls (ADP P < 0.01, collagen P < 0.001, adrenaline P < 0.01, arachidonic acid P < 0.05). These findings strongly suggest an increase of platelet activity in VVI patients.     

Effect of diatrizoate meglumine (Hypaque) on the perilymphatic oxygen tension

The effect of diatrizoate meglumine (Hypaque) upon the perilymphatic oxygenation has been investigated using the polarographic method in cats submitted to various conditions such as normoxia, apnea, hypercapnea and chronically reduced vascularization. The minimal changes of the perilymphatic PO₂ recorded after the injection of Hypaque permit to conclude that this drug has no practical effect upon the oxygenation of the perilymph.     

Permanent Mechanical Catheter Ablation of an Accessory Pathway in a Child

Permanent mechanical ablation of an accessory atrioventricular pathway was observed in an infant during intracavitary electrophysiological mapping. The persistent lack of preexcitation was confirmed during a 15-month follow-up period.     

Ventricular Parasystole: A Chronobiologic Study

Previous works have reported circadian rhythms for several cardiovascular parameters. A chronobiologic rhythm is characterized by: mesor (a rhythm-determined average), amplitude (half difference between the highest and lowest values), and acrophase (timing of high point in degrees and/or in hours) along with 95% confidence limits. We performed 24-hour ECG Holler monitoring in seven patients (mean age, 50.6 years) with ventricular parasystole (VP) in order to determine whether the chronotropic activity of parasystolic foci has a circadian rhythm similar to that of the sinus node. For each Holter recording parasystolic rates (PRs) and heart rates (HRs) were calculated every hour. Furthermore, a mean hourly PR and a mean hourly HR were calculated from the hourly PRs and HRs of the patients. The statistic chronobiologic analysis was done by single and mean cosinor methods. Correlation between mean hourly PR and HR was evaluated by Pearson's V coefficient. A statistically significant rhythm (P < 0.05) was found for the single and mean rhythms both of HR and PR. In our patients, HR had acrophase at 1.27 P.M., mesor at 73.28 beats/min, and amplitude at 9.53 beats/min, whereas PR had acrophase at 1.42 P.M., mesor al 38.31 beats/min, and amplitude at 3.64 beats/ min. Chronobiological data and the high direct correlation between mean hourly HRs and mean hourly PRs (r = 0.96, P < 0.001) indicate a similar circadian variability of the chronotropic activity of sinus nodes and parasystolic foci. Although several hypotheses can be made, responsiveness of parasystolic foci to circadian variations of the autonomic nervous system tone (sympathetic and/or vagal) and/or circulating substances (particularly catecholamines) seems the more probable one for explaining our findings.     

The relationship between sleep and epilepsy: the effect on cognitive functioning in children

Aim The purpose of this review was to examine the possible pathophysiological links between epilepsy, cognition, sleep macro‐ and microstructure, and sleep disorders to highlight the contributions and interactions of sleep and epilepsy on cognitive functioning in children with epilepsy. Method PubMed was used as the medical database source. No language restriction was placed on the literature searches, and citations of relevant studies in the paediatric age range (0–18y) were checked. Studies including a mixed population but with a high percentage of children were also considered. Results The searches identified 223 studies. One reviewer scanned these to eliminate obviously irrelevant studies. Three reviewers scanned the remaining 128 studies and their relevant citations. The review showed that several factors could account for the learning impairment in children with epilepsy: aetiology, electroencephalographic (EEG) discharges, and persistence and circadian distribution of seizures, etc. EEG discharges may affect cognition and sleep, even in the absence of clinical or subclinical seizures. The sleep deprivation and/or sleep disruption affect the neurophysiological and neurochemical mechanisms important for the memory–learning process, but also influence the expression of EEG discharges and seizures. Learning and memory consolidation can take place over extended periods, and sleep has been demonstrated to play a fundamental role in these processes through neuroplastic remodelling of neural networks. Epilepsy and EEG paroxysms may affect sleep structure, interfering with these physiological functions. Interpretation Improvement in the long‐term cognitive–behavioural prognosis of children with epilepsy requires both good sleep quality and good seizure control. The antiepileptic drug of choice should be the one that interferes least with sleep structure and has the best effect on sleep architecture – thus normalizing sleep instability, especially during non‐rapid eye movement sleep.     

Prevention of Sudden Cardiac Death After a First Myocardial Infarction by Pharmacologic or Surgical Antiadrenergic Interventions

Antiadrenergic Interventions and Prevention of Sudden Death after MI. Introduction: Growing evidence points to sympathetic hyperactivity as one critical trigger for life-threatening arrhythmias among postmyocardial infarction patients. Methods and Results: We have evaluated, in a placebo-controlled multicenter study, the efficacy of a β-adrenergic blocking agent (oxprenolol 160 mg) and of a selective left cardiac sympathetic denervation in preventing sudden death in patients with a first and anterior myocardial infarction. Two patient groups were studied. The high-risk group included 144 patients who survived a myocardial infarction complicated by either ventricular tachycardia or fibrillation. The relatively low-risk group included 869 patients whose myocardial infarction did not have these complications; they were allocated only to placebo or oxprenolol. Randomization took place 30 days postmyocardial infarction; mean follow-up was 22 months. In the high-risk group the sudden cardiac death (crude rate) in the placebo subgroup was indeed high (21.3%), and was strikingly reduced to 2.7% and to 3.6% by oxprenolol and by left cardiac sympathetic denervation, respectively (P < 0.05). In the low-risk group the sudden cardiac death (crude rate) in the placebo subgroup was 5.2% and was still reduced by oxprenolol to 1.6% (P < 0.05). The results for total mortality were quite similar to those for sudden death iu both groups. Conclusion: This study, unique for the populations studied and for one of the treatments used, demonstrates that pharmacologic and surgical antiadrenergic interventions significantly reduce sudden cardiac death in postmyocardial infarction patients at high and at low risk. With due consideration to the relatively small size of the high-risk group, it seems reasonable to suggest that left cardiac sympathetic denervation may be considered as a possible alternative for high-risk patients with contraindications to beta blockers. (J Cardiovasc Electrophysiol, Vol 3, pp. 2–16, February 1992)     

Inspiratory stridor in a 12-month-old girl

Congenital tracheal stenosis is a rare disorder, characterized by the presence of focal or diffuse complete tracheal cartilage rings, resulting in a fixed tracheal narrowing. The entity may be seen in isolation or in conjunction with other malformations that include an anomalous right upper lobe bronchus. We here report the case of a 12-month-old girl who had severe bi-segmental congenital tracheal stenosis with the interposition of a tracheal bronchus between the two stenotic segments.