HYPONYCHIUM ABNORMALITIES Congenital Aberrant Hyponychium vs. Acquired Pterygium Inversum Unguis vs. Acquired Reversible Extended Hyponychium: a proposed classification based on origin, pathology and outcome.

BACKGROUND: Pterygium Inversum Unguis (PIU) is a wing-like extended hyponychium associated with the absence of the distal groove. Although a rare condition, it has been described with different names, confusing both the investigator and the reader. OBJECTIVE: We propose a new nomenclature based on tissue origin and pathology, to account for these conditions. 1) Congenital Aberrant Hyponychium 2) Acquired Pterygium Inversum Unguis 3) Acquired Reversible Extended Hyponychium. MAIN OBSERVATIONS: We report a case of a 19-year-old male, with epidermal pigmentation abnormalities, who had painful fingertips of both index fingers and thumbs since he was 13. He therefore let his finger nails grow very long, minimizing painful contact with the hyponychium. Removal of the aberrant hyponychium revealed glomus bodies aggregates with increased nerve fibers. Subsequently after excision of the hyponychium, his pain was resolved. SUMMARY: Congenital, transient or permanent changes in the hyponychium should be named and classified according to tissue origin to avoid nomenclature confusion.

Elephantiasis nostras verrucosa in a patient with systemic sclerosis.

Elephantiasis nostras verrucosa (ENV) is an unusual skin condition characterized by dermal fibrosis and hyperkeratotic verrucous lesions resulting from chronic nonfilarial lymphoedema. The condition is similar to 'elephantiasis tropica', in which elephantiasis develops secondary to filariasis. Lymphatic obstruction can be primary or due to various causes such as surgery, tumour, radiation, congestive heart failure or obesity. Recurrent attacks of cellulitis lead to further impairment of lymphatic drainage, causing permanent swelling, dermal fibrosis and epidermal thickening. We report a case of a 56-year-old man with systemic sclerosis (SS), who presented with painful lesions on both legs, consistent with ENV. He developed extensive, fungating, papillomatous lesions on the skin of the legs, toes and dorsa of the feet over a period of 3 years. Histology revealed dense dermal fibrosis, oedema of the papillary dermis and extensive pseudo-epitheliomatous changes. To our knowledge, this is the first report of ENV in which SS was considered to be the primary cause for the impairment of lymphatic flow.

Chlamydia pneumoniae in atherosclerotic middle cerebral artery.

BACKGROUND AND PURPOSE: Atherosclerotic middle cerebral arteries are frequent sites of thrombosis, leading to stroke. Previous studies have suggested a role for Chlamydia pneumoniae in the pathogenesis of atherosclerosis. However, the presence of this pathogen in atherosclerotic middle cerebral arteries has heretofore not been documented. In the present study, we analyzed atheromatous plaques from middle cerebral arteries for the presence of C pneumoniae. METHODS: Atherosclerotic middle cerebral arteries from 15 cadavers who died of natural causes and corresponding nonatherosclerotic arteries from 4 otherwise healthy trauma victims were examined. Assays for C pneumoniae DNA were carried out by nested polymerase chain reaction (nPCR) specific for the C pneumoniae ompA gene. The presence of the bacterium was assessed by transmission electron microscopy. RESULTS: Five of the 15 atherosclerotic arterial samples and none of the control tissues were positive for C pneumoniae by nPCR. Particles similar in morphology and size to C pneumoniae elementary bodies were detected by transmission electron microscopy in 4 of the 5 nPCR-positive atherosclerotic samples. CONCLUSIONS: The demonstration of C pneumoniae in atherosclerotic middle cerebral arteries is consistent with the hypothesis that this bacterium is involved in acute and chronic cerebrovascular diseases.

Anandamide activates vanilloid receptor 1 (VR1) at acidic pH in dorsal root ganglia neurons and cells ectopically expressing VR1.

The vanilloid receptor type 1 (VR1) is a heat-activated ionophore preferentially expressed in nociceptive neurons of trigeminal and dorsal root ganglia (DRG). VR1, which binds and is activated by capsaicin and other vanilloid compounds, was noted to interact with the endocannabinoid anandamide (ANA) and certain inflammatory metabolites of arachidonic acid in a pH-dependent manner. At pH < or = 6.5 ANA induced (45)Ca(2+) uptake either in primary cultures of DRG neurons or cells ectopically expressing C-terminally tagged recombinant forms of VR1 with an EC(50) = approximately 10 microm at pH 5.5. Capsazepine, a potent antagonist of vanilloids, inhibited ANA-induced Ca(2+) transport in both cell systems. Vanilloids displaced [(3)H]ANA in VR1-expressing cells, suggesting competition for binding to VR1. Ratiometric determination of intracellular free calcium and confocal imaging of the VR1-green fluorescent fusion protein revealed that, at low pH (< or =6.5), ANA could induce an elevation of intracellular free Ca(2+) and consequent intracellular membrane changes in DRG neurons or transfected cells expressing VR1. These actions of ANA were similar to the effects determined previously for vanilloids. The ligand-induced changes in Ca(2+) at pH < or = 6.5 are consistent with the idea that ANA and other eicosanoids act as endogenous ligands of VR1 in a conditional fashion in vivo. The pH dependence suggests that tissue acidification in inflammation, ischemia, or traumatic injury can sensitize VR1 to eicosanoids and transduce pain from the periphery.

Ligand-induced dynamic membrane changes and cell deletion conferred by vanilloid receptor 1.

The real time dynamics of vanilloid-induced cytotoxicity and the specific deletion of nociceptive neurons expressing the wild-type vanilloid receptor (VR1) were investigated. VR1 was C-terminally tagged with either the 27-kDa enhanced green fluorescent protein (eGFP) or a 12-amino acid epsilon-epitope. Upon exposure to resiniferatoxin, VR1eGFP- or VR1epsilon-expressing cells exhibited pharmacological responses similar to those of cells expressing the untagged VR1. Within seconds of vanilloid exposure, the intracellular free calcium ([Ca(2+)](i)) was elevated in cells expressing VR1. A functional pool of VR1 also was localized to the endoplasmic reticulum that, in the absence of extracellular calcium, also was capable of releasing calcium upon agonist treatment. Confocal imaging disclosed that resiniferatoxin treatment induced vesiculation of the mitochondria and the endoplasmic reticulum ( approximately 1 min), nuclear membrane disruption (5-10 min), and cell lysis (1-2 h). Nociceptive primary sensory neurons endogenously express VR1, and resiniferatoxin treatment induced a sudden increase in [Ca(2+)](i) and mitochondrial disruption which was cell-selective, as glia and non-VR1-expressing neurons were unaffected. Early hallmarks of cytotoxicity were followed by specific deletion of VR1-expressing cells. These data demonstrate that vanilloids disrupt vital organelles within the cell body and, if administered to sensory ganglia, may be employed to rapidly and selectively delete nociceptive neurons.