Global spliceosome activity regulates entry into cellular senescence.

Cellular senescence is a state of permanent growth arrest that can ultimately contribute to aging. Senescence can be induced by various stressors and is associated with a myriad of cellular functions and phenotypic markers. Alternative splicing is emerging as a critical contributor to senescence and aging. However, it is unclear how the composition and function of the spliceosome are involved in senescence. Here, using replicative and oxidative stress-induced senescence models in primary human fibroblasts, we report a common shift in the expression of 58 spliceosomal genes at the pre-senescence stage, prior to the detection of senescence-associated ß-galactosidase (SA-ß-gal) activity. Spliceosomal perturbation, induced by pharmacologic and genetic inhibition of splicesomal genes, triggered cells to enter senescence, suggesting a key role as a gatekeeper. Association analysis of transcription factors based on the 58 splicesomal genes revealed Sp1 as a key regulator of senescence entry. Indeed, Sp1 depletion suppressed the expression of downstream spliceosomal genes (HNRNPA3, SRSF7, and SRSF4) and effectively induced senescence. These results indicate that spliceosomal gene sets, rather than a single spliceosomal gene, regulate the early transition into senescence prior to SA-ß-gal expression. Furthermore, our study provides a spliceosome signature that may be used as an early senescence marker.

Evaluation of hematologic profile may be needed for patients treated with oxcarbazepine.

PURPOSE: The major side effects of treatment with oxcarbazepine (OXC) are skin rash and hyponatremia. Hematologic side effects are reported rarely. The aim of this study was to investigate the rate and types of the hematologic side effects of OXC. METHODS: The medical records of 184 patients diagnosed with epilepsy or movement disorder and on OXC monotherapy, at the Department of Pediatrics of Inje University Sanggye Paik Hospital from July 2001 to July 2018, were retrospectively reviewed. RESULTS: Of the 184 patients, 10 (5.4%) developed leukopenia in addition to pancytopenia and 2 (1.0%) developed pancytopenia. Leukopenia developed in 11 days to 14 years after OXC administration and was more frequent in males than in females (male vs. female, 9 vs. 1; Fisher exact test, P<0.05). Of the eight patients with leukopenia alone, 7 continued OXC treatment; 6 improved without intervention; 1 was lost to follow-up; and 1 received a reduced OXC dose, who improved after intervention. Pancytopenia developed within 2 months of initiation of OXC treatment. Both patients initially continued OXC. One improved within 1 month and continued treatment with OXC, but the other showed progression of the side effect, leading to the discontinuation of OXC and subsequent improvement within 1 month. There were no significant differences in the ages of the patients, OXC dose, and duration of OXC treatment between patients with and without these side effects of OXC (P >0.05, t -test). CONCLUSION: OXC-induced leukopenia is not rare and may result in pancytopenia. Patients being treated with OXC should be regularly monitored for abnormal complete blood count profiles.

Facial nerve paralysis due to chronic otitis media: prognosis in restoration of facial function after surgical intervention.

PURPOSE: Facial paralysis is an uncommon but significant complication of chronic otitis media (COM). Surgical eradication of the disease is the most viable way to overcome facial paralysis therefrom. In an effort to guide treatment of this rare complication, we analyzed the prognosis of facial function after surgical treatment. MATERIALS AND METHODS: A total of 3435 patients with COM, who underwent various otologic surgeries throughout a period of 20 years, were analyzed retrospectively. Forty six patients (1.33%) had facial nerve paralysis caused by COM. We analyzed prognostic factors including delay of surgery, the extent of disease, presence or absence of cholesteatoma and the type of surgery affecting surgical outcomes. RESULTS: Surgical intervention had a good effect on the restoration of facial function in cases of shorter duration of onset of facial paralysis to surgery and cases of sudden onset, without cholesteatoma. No previous ear surgery and healthy bony labyrinth indicated a good postoperative prognosis. CONCLUSION: COM causing facial paralysis is most frequently due to cholesteatoma and the presence of cholesteatoma decreased the effectiveness of surgical treatment and indicated a poor prognosis after surgery. In our experience, early surgical intervention can be crucial to recovery of facial function. To prevent recurrent cholesteatoma, which leads to local destruction of the facial nerve, complete eradication of the disease in one procedure cannot be overemphasized for the treatment of patients with COM.

Anatomical consideration of the temporal bone as a pathogenesis of Bell's palsy.

Much controversy surrounds the etiology and management of Bell's palsy, and the pathogenetic mechanisms underlying Bell's palsy remain obscure despite the extensive body of relevant research. The pathological condition of Bell's palsy is almost an inflammatory reaction compressing the facial nerve in the fallopian canal, particularly in the narrowest labyrinthine segment, followed by demyelinating neural change. As one of the best method for the visualization of the inflamed facial nerve in the intratemporal segment, temporal bone CT enable us not only to measure the exact length and thickness of individual segments of the facial nerve canal but also to view variable anatomic variations in the intratemporal facial canal. Some suggest that anatomical variation may predispose the nerve to inflammatory processes and also there can be peculiar structures of the temporal bone that are vulnerable to inflammation or neural compression injury.