The impact of nasal surgery on sleep quality.

OBJECTIVE: Nasal obstruction is considered to be one of the risk factors for obstructive sleep apnea, together with a high arched narrow palate, elongated uvula, malocclusion, and tongue and tonsil size. The impact of nasal obstruction on sleep apnea is controversial, however, and its relation to sleep quality is rarely discussed. The purpose of this study was to investigate the independent effect of nasal obstruction on sleep quality. METHODS: Sixty-nine patients with nasal obstructive symptoms and without sleep apnea episodes were enrolled from September 2018 to August 2019, and compared before and after surgery with thirty-four patients who had benign diseases of the thyroid or parathyroid as a control group, to investigate effects of surgery. Sleep quality was evaluated using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J). All cases were reassessed at three months after surgery. RESULTS: The postoperative PSQI scores in the nasal surgery group were significantly lower than the preoperative scores (p < 0.001). In contrast, there was no statistically significance difference between the pre- and postoperative PSQI scores in the neck surgery group. Difference of PSQI scores before and after surgery in the nasal surgery group was significantly higher than the neck surgery group. CONCLUSIONS: This double-arm study suggests that reduction of nasal disfunction with nasal surgery contributes significantly to sleep quality, in patients who may not have noticed their impaired quality of sleep previously because of their long-term nasal symptoms.

Selected amino acid change encoding Epstein-Barr virus-specific T cell epitope of the LMP2A gene in Japanese nasal NK/T cell lymphoma patients.

Nasal natural killer (NK)/T cell lymphoma is a peculiar lymphoma with a unique immunophenotype. Etiologically, in 1990, the authors first demonstrated the presence of Epstein-Barr virus (EBV) genomes and their products in this lymphoma. EBV-specific cytotoxic T lymphocytes (CTL) are very important in controlling the long-term persistence of EBV infection. Amino acid changes encoding the CTL epitope on the lymphoma cells may result in a reduced CTL response. We focused on two major CTL epitopes SSCSSCPLSK (codon 340 to 349) and FLYALALLLL (codon 356 to 364) of the LMP2A gene and determined the sequence isolated from nasal NK/T cell lymphoma tissues. All isolates from 7 nasal NK/T cell lymphomas showed the same amino acid change from serine to threonine at codon 348 in the CTL epitope SSCSSCPLSK. Threonine or serine substitution at codon 348 was almost equally observed in peripheral blood EBV isolates from healthy individuals in various ethnic origins. The predominant threonine substitution of nasal NK/T cell lymphoma patients may represent disease-associated polymorphism rather than a geographic or race-associated polymorphism. The LMP2A strain including threonine substitution at codon 348 may be selected within tumors and play a role for tumor genesis in Japanese patients with nasal NK/T cell lymphoma through reduced immune recognition.

Sequence variations of Epstein-Barr virus LMP1 gene in nasal NK/T-cell lymphoma.

Nasal natural killer (NK)/T-cell lymphoma is a peculiar lymphoma with an unique immunophenotype. Etiologically, the authors previously first demonstrated the presence of Epstein-Barr virus (EBV) genomes and their products in this lymphoma (Lancet 1990; 335). It is suggested that some of sequence variations such as a 30-bp deletion and multiple base substitutions and as amino acid changes at HLA-A2 restricted CTL epitopes were associated with an increase in tumorigenicity and with a decrease in immune recognition. In this study, we determined full-length of LMP1 sequence isolated from 7 patients with nasal NK/T-cell lymphoma using polymerase chain reaction (PCR) method and compared the sequences with those referred to previous reports. In the carboxyl-terminal site, all 7 patients showed 4 copies of the 11 amino acids repeat (codon 254-302) and 30-bp deletion corresponding to codon 343-352 of the B95-8 strain. Within the NF-kB-activating domains, all 7 patients showed amino acid changes at codon 189 (Gln to Pro), 192 (Ser to Thr) and 212 (Gly to Ser) on either site of the PXQXT (codon 204-208) motif. In the major HLA-A2 restricted T-cell epitope sequence YLLEMLWRL (codon 125-133), all 7 patients showed amino acid changes at codon 126 (Leu to Phe) and 129 (Met to Ile). In the epitopes ALLVLYSFA (codon 51-59), VLFIFGCLL (codon 110-118) and WLLLFLAIL (codon 173-181), several patients showed novel amino acid changes at codon 59 (Ala to Gly), 110 (Val to Leu) and 174 (Leu to Ile), respectively. Although it is still not clear what the most specific and biologic variation of LMP1 gene in nasal NK/T-cell lymphoma is, the sequence data may be valuable on the study for pathogenesis of nasal NK/T-cell lymphoma and EBV molecular epidemiology.