Biopsy of the Parietal Branch of the Superficial Temporal Artery for the Diagnosis of Giant Cell Arteritis.

BACKGROUND: Biopsy of the superficial temporal artery (STA) is central to the diagnosis of giant cell arteritis (GCA), but determining the ideal biopsy site along the course of the STA continues to be a challenge. Traditionally, the frontal branch or preauricular region of the STA is biopsied because of their accessibility, but biopsy at these locations can produce visible cosmetic defects and social disruption that can be distressing to patients, as well as increase the likelihood of adverse events such as injury to the facial nerve. The authors describe a surgical technique of biopsy of the parietal branch of the STA to improve the patient's perioperative and postoperative experience. METHODS: In this retrospective review, 24 patients with clinical suspicion of GCA who underwent biopsy of the parietal branch of the STA were identified. Patients underwent mapping of the branches of the STA with Doppler ultrasound before the procedure. Biopsy of the parietal branch of the STA was conducted using a CO 2 laser. RESULTS: Twenty-four patients underwent biopsy of the parietal branch of the STA. Two patients were diagnosed on histopathology with GCA. All patients tolerated the procedure well and without complications. CONCLUSION: Application of preoperative Doppler ultrasound mapping, use of a CO 2 laser for incisions and hemostasis, and selection of the parietal branch allowed for improved cosmetic outcomes, no associated adverse events, and improved overall patient experience. The authors advocate biopsy of the parietal branch of the superficial temporal artery for the diagnosis of GCA in the absence of contraindications.

Dacryolithiasis: A Review.

PURPOSE: To review and summarize the clinical features, presentations, diagnostic modalities and management of dacryolithiasis. METHODS: A comprehensive PubMed search of all English articles on dacryolithiasis was reviewed. Although this review primarily relied on articles written in English, non-English-language articles that had abstracts translated into English were also reviewed. Data reviewed included epidemiology, pathogenesis, appearance and composition, clinical features, presentations, diagnostic modalities, management of dacryolithiasis and the implications of incidental dacryoliths found during lacrimal surgery. RESULTS: Although an unknown proportion of dacryolithiasis cases may remain asymptomatic; epiphora, acute and/or recurrent dacryocystitis, punctal discharge, and localized swelling are the most common presenting features of dacryolithiasis. It may also present as partial nasolacrimal duct obstruction. Dacryoliths exhibit a variety in external appearances. While some minimally invasive techniques for the removal of dacryoliths have been described, dacryocystorhinostomy with removal of the dacryoliths remain the most effective treatment in cases of symptomatic dacryolithiasis. The expression and production of certain proteins and peptides, namely those of the trifoil factor family play a significant role in the pathogenesis of dacryoliths. CONCLUSIONS: The management of dacryolithiasis is driven by the goal of resolution of secondary obstruction and/or inflammation. Although a large number of dacryoliths are incidentally found during dacryocystorhinostomy, certain clinical features such as unilateral sac distension, particularly those with a palpable firm medial canthal mass, might lead one to have a high index of suspicion. It remains unclear if the incidental finding of a dacryolith during a dacryocystorhinostomy has a favorable prognostic value.

Minor introns are embedded molecular switches regulated by highly unstable U6atac snRNA.

Eukaryotes have two types of spliceosomes, comprised of either major (U1, U2, U4, U5, U6) or minor (U11, U12, U4atac, U6atac; <1%) snRNPs. The high conservation of minor introns, typically one amidst many major introns in several hundred genes, despite their poor splicing, has been a long-standing enigma. Here, we discovered that the low abundance minor spliceosome's catalytic snRNP, U6atac, is strikingly unstable (t½<2 hr). We show that U6atac level depends on both RNA polymerases II and III and can be rapidly increased by cell stress-activated kinase p38MAPK, which stabilizes it, enhancing mRNA expression of hundreds of minor intron-containing genes that are otherwise suppressed by limiting U6atac. Furthermore, p38MAPK-dependent U6atac modulation can control minor intron-containing tumor suppressor PTEN expression and cytokine production. We propose that minor introns are embedded molecular switches regulated by U6atac abundance, providing a novel post-transcriptional gene expression mechanism and a rationale for the minor spliceosome's evolutionary conservation. DOI:http://dx.doi.org/10.7554/eLife.00780.001.