Truncating CLCN1 mutations in myotonia congenita: variable patterns of inheritance.

Introduction: Myotonia congenita due to protein truncating CLCN1 mutations is associated with variable patterns of inheritance.

Methods: Three family kindreds are described, all of whom possess protein truncating mutations (Y33X, fs503X, R894X). One lineage also has coexistent R894X, A313T, and A320V mutations.

Severe case and literature review of primary erythromelalgia: novel SCN9A gene mutation.

Erythromelalgia is a rare clinical syndrome characterized by intermittent heat, redness, swelling and pain more commonly affecting the lower extremities. Symptoms are mostly aggravated by warmth and are eased by a cold temperature. In some cases, symptoms can be very severe and disabling.

Unilateral myokymia of the tongue after radiation therapy for cervical nodal melanoma.

Hypoglossal neuropathy with associated myokymia as a delayed effect of radiation is a rare occurrence, presumably due to the relative resistance of cranial nerves to injury from irradiation. The authors describe the first case of myokymia of the unilateral tongue with myokymic discharges on needle electromyography after hypofractionated radiation therapy for an extracranial melanoma of the neck. The earlier onset of myokymia than previous cases may represent more direct radiation exposure due to radiation site or the higher radiation dosage administered for treatment of melanomas.

Comparison of accidental and nonaccidental traumatic head injury in children on noncontrast computed tomography.

Objective: Mixed-density convexity subdural hematoma and interhemispheric subdural hematoma suggest nonaccidental head injury. The purpose of this retrospective observational study is to investigate subdural hematoma on noncontrast computed tomography in infants with nonaccidental head injury and to compare these findings in infants with accidental head trauma for whom the date of injury was known.

Patients And Methods: Two blinded, independent observers retrospectively reviewed computed tomography scans with subdural hematoma performed on the day of presentation on 9 infant victims of nonaccidental head injury (mean age: 6.

Inhibitory network properties shaping the light evoked responses of cat alpha retinal ganglion cells.

Cat retinal ganglion cells of the Y (or alpha) type respond to luminance changes opposite those preferred by their receptive-field centers with a transient hyperpolarization. Here, we examine the spatial organization and synaptic basis of this light response by means of whole-cell current-clamp recordings made in vitro. The hyperpolarization was largest when stimulus spots approximated the size of the receptive-field center, and diminished substantially for larger spots.