Brain 2017 10;140(10):2570-2585

Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.

See Basbaum (doi:10.1093/brain/awx227) for a scientific commentary on this article. Peripheral neuropathic pain arises as a consequence of injury to sensory neurons; the development of ectopic activity in these neurons is thought to be critical for the induction and maintenance of such pain. Read More

Indian Dermatol Online J 2017 May-Jun;8(3):201-204

Department of Pathology, PGIMER, Dr. RML Hospital, New Delhi, India.

Cutaneous meningiomas are rare tumors. These are ectopic meningothelial cells located in the dermis and subcutis, and are usually seen on the scalp. Here, we report the case of a 40-year-old woman who presented with a slowly growing asymptomatic mass over the scalp in the right parieto-occipital region. Read More

World Neurosurg 2017 Feb 27;98:882.e9-882.e14. Epub 2016 Oct 27.

Division of Plastic Surgery, Department of Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA. Electronic address:

Background: Craniotomies for trauma are associated with a significant risk of wound complications. We report a case in which a chronic nonhealing draining sinus was caused by an ectopic epidermal lining deep to the craniotomy bone flap, adherent to the underlying dura.

Case Description: A 61-year-old man was examined for a 3-year-old, nonhealing scalp wound resulting after a traumatic brain injury. Read More

J Comp Pathol 2016 Jul 17;155(1):50-4. Epub 2016 Jun 17.

Servicio de Diagnóstico Anatomopatológico Veterinario HISTOVET, Avda. Països Catalans 12D, Sant Quirze del Vallès, Barcelona, Spain.

A 3-month-old, male European shorthair kitten exhibited an ill-defined, soft mass on the skin of the frontal head, which was present since birth. The surgically resected tissue was representative of a discrete dermal and subcutaneous mass comprising islands of neurons, glial and meningothelial elements, sometimes atypical or dysplastic, separated by dense collagenous connective tissue. There was no evident connection between this tissue and the brain. Read More

J Med Case Rep 2014 Oct 16;8:346. Epub 2014 Oct 16.

Section of Oncopathology and Regenerative Biology, Department of Pathology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, Miyazaki 889-1692, Japan.

Introduction: Paragonimiasis is a food-borne infection caused by Paragonimus parasites. The lungs and pleura are the primary sites for the infection; however, ectopic infection can occur in other organs such as skin, liver and brain. It is difficult to make a diagnosis of ectopic paragonimiasis due to an ignorance of, and unfamiliarity with the disease. Read More

PLoS One 2013 14;8(1):e53970. Epub 2013 Jan 14.

Section of Dermato-Oncology, Department of Dermatology, University of Tuebingen, Tuebingen, Germany.

Background: A primary cutaneous melanoma will not kill the patient, but its metastases. Since in vitro studies on melanoma cells in 2-D cultures do often not reflect reality, 3-D models might come closer to the physiological situation in the patient during cancer initiation and progression.

Methodology/principal Findings: Here, we describe the chick embryo model for in vivo studies of melanoma cell migration and invasion. Read More

Cell 2012 Aug;150(4):816-30

Division of Molecular Medicine and Genetics, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109, USA.

Germline mutations in the RAS/ERK signaling pathway underlie several related developmental disorders collectively termed neuro-cardio-facial-cutaneous (NCFC) syndromes. NCFC patients manifest varying degrees of cognitive impairment, but the developmental basis of their brain abnormalities remains largely unknown. Neurofibromatosis type 1 (NF1), an NCFC syndrome, is caused by loss-of-function heterozygous mutations in the NF1 gene, which encodes neurofibromin, a RAS GTPase-activating protein. Read More

Nat Neurosci 2008 Nov 12;11(11):1283-93. Epub 2008 Oct 12.

Department of Medicine, University of California San Diego, La Jolla, California 93093, USA.

We used conditional knockout strategies in mice to determine the developmental events and gene expression program regulated by the LIM-homeodomain factor Islet1 in developing sensory neurons. Early development of the trigeminal and dorsal root ganglia was grossly normal in the absence of Islet1. From E12. Read More

Neuroscience 2002 ;111(4):709-38

School of Biomedical Sciences, Faculty of Health and Hunter Medical Research Institute, The University of Newcastle, Newcastle, NSW 2308, Australia.

Studies of the effects of peripheral and central lesions, perceptual learning and neurochemical modification on the sensory representations in cortex have had a dramatic effect in alerting neuroscientists and therapists to the reorganizational capacity of the adult brain. An intriguing aspect of some of these investigations, such as partial peripheral denervation, is the short-term expression of these changes. Indeed, in visual cortex, auditory cortex and somatosensory cortex loss of input from a region of the peripheral receptor epithelium (retinal, basilar and cutaneous, respectively) induces rapid expression of ectopic, or expanded, receptive fields of affected neurons and reorganization of topographic maps to fill in the representation of the denervated area. Read More

Cancer Res 2000 Apr;60(7):1800-4

Department of Dermatology, Massachusetts General Hospital and Dana-Farber/Partners CancerCare, Boston 02114, USA.

Both inactivation of the tumor suppressor gene, PTEN/MMAC1, and oncogenic activation of RAS have been described in human cutaneous melanoma. In mice, activation of a RAS-containing pathway is a necessary step in the pathogenesis of murine melanomas. Because PTEN negatively regulates on the downstream effects of phosphatidylinositol-3-kinase (PI3-K), we hypothesized that the loss of PTEN/MMAC1 and the activation of RAS may be largely equivalent because RAS is a known positive upstream regulator of PI3-K. Read More

Brain Res 1999 Apr;824(2):218-23

Department of Anatomy and Cell Biology, Hadassah-Hebrew University Dental and Medical Schools, Jerusalem 91120, Israel.

It is difficult to know which afferent types preferentially develop ectopic firing characteristics following nerve injury because axotomy disconnects the sensory receptor ending from the remainder of the afferent neuron. We compared the prevalence of ectopic firing originating in nerve-end neuromas of nerves serving muscle and skin in the rat. Spontaneous firing was much more prevalent in the injured medial gastrocnemius nerve, a hindlimb muscle nerve, than in the saphenous and sural nerves which primarily innervate hindlimb skin. Read More

Brain 1998 May;121 ( Pt 5):851-9

Department of Neurology, Prince of Wales Hospital, Randwick, Sydney, Australia.

In normal subjects, the strength-duration time constant is longer for cutaneous afferents than for motor axons, probably because the former express a greater non-inactivating (persistent) Na+ conductance that is active at threshold. Using a threshold-tracking system the strength-duration properties of cutaneous afferents and motor axons were recorded from 23 patients with amyotrophic lateral sclerosis, and compared with those of 32 healthy subjects. In control subjects and patients, the strength-duration time constant of sensory fibres declined with age, and there was no difference between the two groups when age was taken into account. Read More

Arch Pathol Lab Med 1998 Jan;122(1):97-9

Department of Pathology, Harbor-UCLA Medical Center, Torrance, Calif 90509, USA.

A cutaneous meningioma of the external auditory canal occurred in a 48-year-old Filipino woman who had undergone subtotal resection of a dural-based intracranial meningioma at the ipsilateral cerebellopontine angle 36 months previously. Radiologic findings demonstrated a recurrence of intracranial meningioma with surface erosion and heterogeneous densities of the mastoid bone, without extension to the area of the external auditory canal. Meningioma in the external ear canal is extremely rare. Read More

Pediatrics 1995 Aug;96(2 Pt 1):309-13

Department of Pediatrics, Medical College of Wisconsin, Milwaukee, USA.

Objective: To call attention to a cutaneous marker for neural tube closure defects of the scalp, the "hair collar" sign. This finding consists of a ring of long, dark, coarse hair surrounding a midline scalp nodule.

Methods And Results: Four children with small congenital scalp nodules and the hair collar sign were studied from the standpoint of clinical findings, radiologic scans, and histology of the excised nodules. Read More

Nihon Kyobu Shikkan Gakkai Zasshi 1992 Jun;30(6):1125-30

Third Department of Medicine, Oita Medical University, Japan.

Patients with Paragonimiasis westermani show a typical ring form or nodular shadow on chest X-ray, cough, sputum, and hemosputum. Recently, case reports of Paragonimiasis westermani, accompanied by pneumothorax and pleural effusion, as for Paragonimiasis miyazakii, have been increasing. Paragonimus westermani often causes an ectopic infection in various organs such as the peritoneal cavity, pleural cavity, pericardium, liver, adrenal gland and brain. Read More

Brain 1991 Feb;114 ( Pt 1B):527-40

Department of Clinical Neurophysiology, Prince Henry Hospital, Sydney, NSW, Australia.

Anxiety can induce hyperventilation, and the resultant hypocapnia and hypocalcaemia can lead to paraesthesiae and tetany. To define the nature of the disturbance created in peripheral nerve, the excitability of cutaneous and motor axons was monitored in 6 normal subjects requested to hyperventilate until paraesthesiae developed in the hands, face and trunk. This occurred when alveolar PCO2 (PACO2) had declined on average by 20 mmHg. Read More

Brain 1989 Feb;112 ( Pt 1):147-64

Department of Neurology, Prince Henry Hospital, Little Bay, NSW, Australia.

Prolonged high-frequency stimulation of cutaneous nerves can result in paraesthesiae that begin 20 to 30 s after the end of the train and last for 5 to 10 min. In the present experiments the effects of such stimulation on the excitability of human cutaneous afferents and on their refractory and supernormal periods were measured to determine whether these changes could explain the postactivation paraesthesiae. Attention was focused on the axons of lowest threshold (1. Read More

Brain 1987 Aug;110 ( Pt 4):1015-31

Department of Neurology, Prince Henry Hospital, Little Bay, NSW, Australia.

The excitability of cutaneous afferents in the median nerve of 20 normal human subjects was investigated using a supramaximal conditioning stimulus and a submaximal test stimulus that produced an afferent volley of 20 to 40% of maximum. The intensity of the test stimuli was 1.1 to 1. Read More

Brain Res 1982 Dec;253(1-2):57-63

The properties of junctions formed de novo in ectopic regions of muscle were studied and compared to those of endplates reinnervated after nerve crush and to normals. The nerve to the frog cutaneous pectoris muscle was transposed and implanted onto an endplate-free (ectopic) region of that muscle, while the endplate-containing portion was excised. New synapses, which subsequently formed in the remaining muscle segment, were studied morphologically and physiologically at postoperative times from approximately 3 weeks to a year. Read More