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Background Nitric oxide (NO) is believed to participate in the regulation of airway clearance and non-specific cellular immunity. Recent studies have suggested that airway epithelial cells of allergic and non-allergic individuals may differ in their ability to produce this molecule. Objective The aim of this study was to detect the difference in NO production in human nasal epithelial cells between normal subjects and patients with perennial allergic rhinitis (AR), and to assess the relationship between the expression of nitric oxide synthase (NOS) isoforms and the severity of the disease. Methods Nasal epithelial cells were obtained from the inferior turbinate. The expression of mRNAs encoding constitutive endothelial NOS (eNOS) and inducible NOS (iNOS) was studied by reverse transcription-polymerase chain reaction (RT-PCR). Direct NO production in living cells was visualized and quantified by a fluorescent indicator, DAF-2 DA. Results RT-PCR analysis demonstrated that AR patients with a RAST score of 5 or 6 showed significant increases in the levels of iNOS mRNA and slight reductions in those of eNOS mRNA. Patients with a RAST score of 2–4 also revealed the same tendency however, the difference was not significant. DAF-2 DA imaging demonstrated that epithelial cells, especially the ciliated cells, produced a larger amount of NO than non-epithelial inflammatory cells. Preincubation with L-NAME resulted in an approximate 40% decrease in both groups. Conclusion These results directly indicate that nasal epithelial cells of AR patients overall produce higher levels of NO through the concomitant expression of different NOS isoforms. Continuous NO production by the epithelial cells in normal subjects further support the hypothesis that NO derived from epithelium may play dual roles in the regulation of nasal airway clearance and in the host defense. In addition, the use of DAF-2 DA provides a reliable method to visualize and quantify the direct NO production of living cells. [ABSTRACT FROM AUTHOR]

Objectives: A panel of cytokines has been found to be important for eosinophil accumulation and activation in nasal polyps. The aims of this study were to ascertain whether the activation of nuclear factor-kappa B (NF-kappaB) occurred in the polyp epithelium, and to examine the relationship between the degree of activation and local cytokine gene expression., Study Design/methods: Nasal polyp specimens were obtained from 26 untreated patients. The proportion of nuclear translocation of the NF-kappaB p50 subunit in the polyp epithelium was quantitatively analyzed by a combination of fluorescent immunohistochemistry and a laser scanning confocal microscope image system. The levels of GM-CSF, IL-5, IL-8, IL-16, and eotaxin mRNA expression in the same speci-mens were measured using reverse transcription-polymerase chain reaction., Results: Both cytoplasmic and nuclear localization of the p50 subunit was observed mainly in the epithelial layer in all specimens. The percentages of epithelial cells with nuclear translocation ranged from 4.5% to 40.5% (median, 18%). Significant correlations were observed between the degree of epithelial NF-kappaB activation and the levels of IL-8, IL-16, and eotaxin mRNA expression (r = 0.468, 0.47, and 0.739, respectively)., Conclusion: The activation of NF-kappaB in the nasal polyp epithelium is responsible for the recruitment of inflammatory cells, particularly eosinophils, through the initiation of the transcriptional pathway of the related cytokines. The increased NF-kappaB activity in the polyp epithelium may reflect hypersensitivity to unknown stimuli.

Objectives/hypothesis: Laser surgery of the inferior turbinates has become a popular surgical treatment for patients with allergic rhinitis, particularly for those who have persistent nasal obstruction and do not respond well to pharmacological therapy. The aim of this study was to investigate the effects of the laser surgery on local cytokine gene expression at the mucosal surface in relation to the improvement of nasal symptoms., Study Design: A prospective analysis of 25 patients with allergic rhinitis caused by the house dust mite who underwent laser surgery twice with a 1-month interval on an outpatient basis. Fifteen healthy volunteers served as normal control subjects., Methods: Improvement of the nasal symptoms was evaluated on a graded scale. Nasal mucosal cells were obtained by brushing from the inferior turbinate at each visit. The expression of messenger RNA (mRNA) encoding granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-6, IL-8, RANTES (regulated on activation, normal T-cell expressed and secreted), and eotaxin was semiquantitatively analyzed by reverse transcription-polymerase chain reaction (RT-PCR)., Results: Two months after treatment, the nasal symptom scores significantly decreased from baseline. The decrease was most apparent in nasal obstruction. RT-PCR analysis revealed that a significant decrease in IL-8 and RANTES expression (P < .001 and P = .012, respectively) was observed after successive laser treatment, and the reduction in these cytokines was significantly correlated. On the other hand, mRNA expression of GM-CSF, IL-6, and eotaxin remained unchanged., Conclusions: This study provided evidence that the expression of local inflammatory cytokines can be attenuated in part by CO2 laser treatment, which may be closely related to the clinical effectiveness of this procedure.

Objective: Periarticular osteopenia is frequently observed in rheumatoid arthritis (RA). Bone loss has been considered to be at least partly due to inadequate bone formation, which in turn, is largely dependent on the number of osteoblasts and the osteoblastic activity. Normal human somatic cells undergo a finite number of cell divisions and ultimately enter a nondividing state called replicative senescence. It has been proposed that the telomere, the terminal sequence of chromosomes, is the mitotic clock that triggers senescence. In the present study, we sought to clarify the relationship between periarticular osteopenia and osteoblast replicative senescence in RA., Methods: We examined age-related changes in cellular activity (alkaline phosphatase activity, osteocalcin and C-terminal type I procollagen secretion, and cAMP response to parathyroid hormone), replicative capacity, and senescent cell expression in osteoblasts from periarticular bone samples obtained from 15 patients with RA and 15 age-matched patients with osteoarthritis (OA). Cellular replicative capacity was analyzed by the mean telomere length and in vitro remaining replicative lifespan of the cells., Results: In both OA and RA groups, the cell proliferation rate, the levels of osteoblastic markers, mean telomere length, and replicative lifespan in osteoblastic cells gradually decreased with the increasing age of the donor. The percentage of senescent osteoblastic cells in the periarticular bone increased with age in both groups, and the rate of expression of senescent cells was higher in RA patients than in age-matched OA patients. The osteoblastic activities and replicative capacity of osteoblastic cells from RA patients were lower than those from OA patients at any donor age. The age-related decreases in the osteoblastic activity and replicative capacity of osteoblastic cells from periarticular bone were greater in RA patients than in OA patients., Conclusion: Our results suggest that osteoblast replicative senescence in periarticular bones occurs more rapidly with aging in RA than in OA patients and contributes to periarticular osteopenia in RA.

The incidence of black-pigmented rods (BPRs), especially Prevotella intermedia and Prevotella nigrescens, in periodontal health and disease were examined. Furthermore, the degradative enzyme activities of P. intermedia were compared among the strains from periodontal health and disease. Microbiological specimens were collected from subgingival crevice or periodontal pocket by paper point. The BPRs were found in 71.1% of periodontally healthy subjects (n=45), and in 47.1% of healthy sites (n=34) and 87.8% of active sites (n=41) among periodontally diseased patients. Porphyromonas gingivalis was detected only in active sites of periodontally diseased patients (17.8% of 180 strains). P. intermedia was the predominant BPR in both healthy and active sites (37.3 and 41.7%, respectively) of the patients. However, P. nigrescens was the predominant BPR (70.5% of 173 strains) in periodontally healthy subjects. The enzyme activities of esterase, esterase-lipase, acid-phosphatase and alpha-fucosidase of P. intermedia strains isolated from active sites in patients were significantly higher (P<0.05) than those of healthy subjects. The results suggest that P. intermedia might increase the activity of degradative enzymes under a certain condition and support the progression of periodontitis.