TBHQ Alleviates Particulate Matter-Induced Pyroptosis in Human Nasal Epithelial Cells.

Pyroptosis represents a type of cell death mechanism notable for its cell membrane disruption and the subsequent release of proinflammatory cytokines. The Nod-like receptor family pyrin domain containing inflammasome 3 (NLRP3) plays a critical role in the pyroptosis mechanism associated with various diseases resulting from particulate matter (PM) exposure. Tert-butylhydroquinone (tBHQ) is a synthetic antioxidant commonly used in a variety of foods and products. The aim of this study is to examine the potential of tBHQ as a therapeutic agent for managing sinonasal diseases induced by PM exposure. The occurrence of NLRP3 inflammasome-dependent pyroptosis in RPMI 2650 cells treated with PM < 4 µm in size was confirmed using Western blot analysis and enzyme-linked immunosorbent assay results for the pyroptosis metabolites IL-1ß and IL-18. In addition, the inhibitory effect of tBHQ on PM-induced pyroptosis was confirmed using Western blot and immunofluorescence techniques. The inhibition of tBHQ-mediated pyroptosis was abolished upon nuclear factor erythroid 2-related factor 2 (Nrf2) knockdown, indicating its involvement in the antioxidant mechanism. tBHQ showed potential as a therapeutic agent for sinonasal diseases induced by PM because NLRP3 inflammasome activation was effectively suppressed via the Nrf2 pathway.

Eupatilin Inhibits Reactive Oxygen Species Generation via Akt/NF-κB/MAPK Signaling Pathways in Particulate Matter-Exposed Human Bronchial Epithelial Cells.

BACKGROUND: Eupatilin is an active flavon extracted from the Artemisia species and has properties such as antioxidant, anti-inflammatory, and anti-cancer. We examined the effect of eupatilin using fine particulate matter (FPM) and human bronchial epithelial cell line (BEAS-2B) to confirm the potential of eupatilin as a therapeutic agent for respiratory diseases caused by FPM. METHODS: Reactive oxygen species (ROS) levels were checked by flow cytometry to identify if FPM and eupatilin affect ROS production. Western blotting was performed to identify the mechanism of action of eupatilin in FPM-exposed BEAS-2B cells. RESULTS: When cells were exposed to FPM above 12.5 µg/mL concentration for 24 h, ROS production increased significantly compared to the control. When eupatilin was added to cells exposed to FPM, the ROS level decreased proportionally with the eupatilin dose. The phosphorylation of Akt, NF-κB p65, and p38 MAPK induced by FPM was significantly reduced by eupatilin, respectively. CONCLUSION: FPM cause respiratory disease by producing ROS in bronchial epithelial cells. Eupatilin has been shown to inhibit ROS production through altering signaling pathways. The ROS inhibiting property of eupatilin can be exploited in FPM induced respiratory disorders.

Urban particulate matter regulates tight junction proteins by inducing oxidative stress via the Akt signal pathway in human nasal epithelial cells.

Recent studies have revealed that increased reactive oxidative stress (ROS) induced by particulate matter (PM) affects tight junction (TJ) functions; however, the molecular mechanisms underlying this effect have not been evaluated fully. Cultured human epithelial cells obtained from inferior turbinate tissues were exposed to an urban PM (UPM) standard reference material (SRM 1648a). Intracellular ROS level and expression of proinflammatory cytokines and TJ proteins were examined. Expression level of phosphorylated (p)-Akt, p38, p65 were compared between exposed and unexposed cells. Cells were pretreated with the ROS scavenger N-acetylcysteine (NAC) or Akt inhibitor MK-2206 before exposure to determine whether the changes in cellular ROS and TJ protein expression could be reversed. Exposure to UPM significantly increased ROS levels and inflammatory cytokine expression levels, and decreased expression of TJ proteins zonula occludins (ZO)-1, occludin, claudin-1, and E-cadherin. UPM exposure increased p-Akt, p-p38, and p65 expression levels, and NAC pretreatment reversed these effects. Akt inhibition decreased UPM-induced ROS formation and p38 and p65 protein phosphorylation, and restored the decreased ZO-1 and E-cadherin expression. Akt inhibition and ROS scavenging may provide targets for maintaining epithelial integrity by restoring decreased TJ protein expression during exposure to UPM.

Activation of the Nrf2/HO-1 pathway by curcumin inhibits oxidative stress in human nasal fibroblasts exposed to urban particulate matter.

BACKGROUND: Particulate matter (PM) can cause various negative acute and chronic diseases of the respiratory system, including the upper airways. Curcumin has been reported to have anti-inflammatory and anti-oxidative effects; therefore, we investigated the effects of curcumin on nasal fibroblasts exposed to urban PM (UPM). METHODS: Samples of inferior turbinate tissue were obtained from six patients. Flow cytometry was used to assess the levels of reactive oxygen species (ROS) following the treatment of nasal fibroblasts with UPM and/or curcumin. We evaluated the effects of UPM and/or curcumin on the expression of phosphorylated ERK, Nrf2, HO-1, and SOD2 in fibroblasts by Western blotting. RESULTS: When UPM was applied to nasal fibroblasts, ROS production was significantly increased in a dose-dependent manner. UPM-exposed fibroblasts caused the activation of ERK to increase HO-1 expression and decrease SOD2 expression. Treatment with curcumin reduced the UPM-mediated increase in ROS; this decrease in ROS occurred in a dose-dependent manner. The UPM-induced activation of ERK was inhibited by curcumin. Nrf2 production was also promoted to increase the expression of HO-1 and SOD2 by curcumin. CONCLUSION: Curcumin reduced ROS production caused by UPM in human nasal fibroblasts in a dose-dependent manner, suggesting that curcumin has anti-oxidative effects and may be useful in the treatment of nasal diseases caused by UPM, such as allergic and chronic rhinitis.

In vivo Oxygen Condition of Human Nasal Inferior Turbinate-Derived Stem Cells in Human Nose.

BACKGROUND AND OBJECTIVE: Human nasal inferior turbinate-derived stem cells (hNTSCs) have been considered as a potent and useful source for regenerative medicine. To most effectively mimic the native environment of inferior turbinate could be very effective to hNTSCs biology. Thus, the purpose of this study was to evaluate partial pressure of oxygen (ppO2) and temperature in inferior turbinate. METHODS: Ten patients were enrolled who underwent endoscopic endonasal transsphenoidal skull base tumor surgery between January 2014 and December 2015. The commercially available OxyLab pO2 monitor gauges the ppO2 and temperature using a fluorescence quenching technique. Also, hNTSCs were isolated from 10 patients and cultivated under hypercapnic condition (5, 10, and 15%) to mimic hypoxic intranasal conditions. RESULTS: The measured oxygen concentration in submucosa tissue was higher than that at the surface of the inferior turbinate and the temperature in submucosa tissue was higher than the value at the surface of inferior turbinate. The patterns of proliferation were significantly different according to hypercapnic cultivation conditions and there were statistically significant decreased proliferation rates after the exposure of higher CO2 over a period of 5 days. CONCLUSIONS: Intranasal turbinate tissue showed the hypoxia state in concordance with the result of the other tissues or organs. However, indirectly induced hypoxia influenced the influence on the hNTSCs proliferation negatively. Further study is needed to mimic the real hypoxic state, but our results could be used to optimize the culture environment of hNTSCs, thereby producing the stem cells for regenerative therapies.

Effect of fluticasone propionate on human nasal fibroblasts exposed to urban particulate matter.

OBJECTIVE: Particulate matter (PM), which contains organic compounds and toxic metals, is the major cause of air pollution. PM enters the body, causing various health problems. Although the effects of PM on the lower respiratory tract have been extensively investigated, the effects on the upper respiratory tract (including the nasal cavity) require further evaluation. To investigate the effect of fluticasone propionate (FP) on nasal fibroblasts exposed to UPM. METHODS: Samples of inferior turbinate tissue were obtained from six patients. The fibroblasts isolated from these samples were exposed to UPM and/or FP. The expression of interleukin (IL)-6, CXC chemokine ligand (CXCL) 1, IL-1ß, and tumour necrosis factor-alpha (TNF-α) in nasal fibroblasts was analysed using real-time PCR and enzyme-linked immunosorbent assays. The protein levels of nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) were analysed by western blotting. RESULTS: FP reversed the UPM-induced reduction in cell viability. The mRNA and protein levels of IL-6, CXCL1, IL-1ß, and TNF-α were significantly increased by UPM. FP reversed the UPM-induced increases in the protein levels of NF-κB and phosphorylated-STAT3 in a dose-dependent manner. In addition, TNF-α, an inducer of NF-κB, reversed the FP-induced reduction in the levels of signalling molecules. CONCLUSION: UPM induces the expression of IL-6, CXCL1, IL-1ß, and TNF-α in nasal fibroblasts and this effect is reversed by FP via the STAT3 and NF-κB signalling pathways. These results suggest that FP has therapeutic potential for nasal diseases related to UPM, such as allergic and chronic rhinitis.

Protective effects of α-lipoic acid on cultured human nasal fibroblasts exposed to urban particulate matter.

BACKGROUND: Exposure to urban particulate matter (UPM) has been studied as a cause of various health problems. Although the association between UPM and the respiratory tract has been well studied, further research is required to characterize the effects of UPM on the upper respiratory tract. We investigated the effects of UPM-induced reactive oxygen species (ROS) production on cultured human nasal fibroblasts, as well as the protective effects of α-lipoic acid (ALA) on ROS production and the underlying signaling pathways involved in ROS inhibition. METHODS: Human turbinate tissue specimens were collected from 6 patients. The effects of UPM on the viability of cultured nasal fibroblasts were determined. A fluorescent malondialdehyde assay was used to measure ROS levels. Real-time reverse transcription polymerase chain reaction was used to measure the messenger RNA levels of genes encoding Nrf2, the antioxidant response elements (AREs) (HO-1, NQO1), and the proinflammatory cytokines (interleukin-6 and interleukin-8) before and after ALA treatment. Western blotting analyses were used to measure nuclear and cytosolic Nrf2 and AREs. RESULTS: UPM reduced cell viability and increased ROS expression in nasal fibroblasts. ALA treatment decreased ROS production in UPM-exposed fibroblasts via the Nrf2, HO-1, and NQO-1 pathways. Also, ALA treatment abrogated increases in the interleukin-6 and -8 levels induced by UPM in nasal fibroblasts. CONCLUSION: UPM exposure resulted in increased ROS production in nasal fibroblasts. ALA treatment inhibited this increase via the Nrf2 pathway, suggesting that ALA may have a protective effect against rhinitis caused by ROS expression induced by exposure to UPM.

The effect of urban particulate matter on cultured human nasal fibroblasts.

BACKGROUND: Exposure to urban particulate matter (UPM) has been linked to aggravation of various health problems. Although the effects of UPM on the lower respiratory tract have been extensively studied, more research is required on the impact of UPM on the upper respiratory tract and the underlying mechanisms. Thus, we investigated the cytotoxic effects of UPM on cultured human nasal fibroblasts, the underlying signaling pathways involved, and changes in cytokine levels. METHODS: Human turbinate tissue specimens were collected during partial turbinectomies performed on 6 patients, and then cultured. The effect of UPM on nasal fibroblast viability was explored. Real-time reverse transcription-polymerase chain reaction was used to measure the mRNA levels of genes encoding cytokines and chemokines (interleukin [IL]-4, IL-6, IL-8, and tumor necrosis factor-α) before and after 24 hours of UPM treatment. Enzyme-linked immunosorbent assays were employed to measure IL-6 and IL-8 levels. The status of the p38 and nuclear factor (NF)-κB signaling pathways was analyzed by Western blotting. RESULTS: UPM reduced cell viability in a dose-dependent manner and increased IL-6 and IL-8 expression at both the mRNA and protein levels. UPM induced the phosphorylation of p38 and NF-κB p65; inhibitors of the actions of these proteins repressed phosphorylation and the expression of IL-6 and IL-8. CONCLUSION: UPM induced IL-6 and IL-8 expression by fibroblasts via p38 and NF-κB classical signaling, suggesting that UPM can induce or aggravate allergic and/or chronic rhinitis.

Evaluation of characteristic of human turbinate derived mesenchymal stem cells cultured in the serum free media.

We evaluated the effect of serum-free and xeno-cultivation (SFXFM) on the characterization, proliferation, and differentiation properties of human nasal stem cells (airway tissue; hTMSCs). hTMSCs were isolated from 10 patients, after which patient samples were separated into two groups, an SFXFM group and a control group. The control group was treated with bovine serum-containing medium. FACS analysis revealed that SFXFM-cultured hTMSCs maintained a characteristic mesenchymal stem cell phenotype. hTMSC proliferation was not influenced by SFXFM. In addition, upregulation of IL-8 and GM-CSF and downregulation of RANTES expression were shown in response to SFXFM. Moreover, two-lineage differentiation properties (osteocyte and adipocyte) of hTMSCs were enhanced under SFXFM. Finally, the genetic stability of SFXFM-cultured hTMSCs was demonstrated by normal karyotype results. SFXFM enables good expansion, multipotentiality, and normal genotype maintenance of MSCs. Moreover, this approach serves as a substitute to conventional media for the cultivation of capable MSCs for upcoming medical applications.

Does the Effect of Inferior Turbinate Outfracture Persist?

BACKGROUND: To resolve nasal obstruction in rhinoplasty, inferior turbinate outfracture is performed widely alone or combined with other procedures. There are conflicting reports on the effect of inferior turbinate outfracture. This study evaluated the persistence of morphologic changes after inferior turbinate outfracture. METHODS: This retrospective study enrolled 55 patients who underwent inferior turbinate outfracture without septal surgery to approach the sphenoid sinus for brain tumor removal. Coronal paranasal sinus computed tomographic images obtained preoperatively and 6 months postoperatively were compared. The authors measured the shortest distance from the median line to the medial border of the conchal bone and the shortest distance from the medial border of the conchal bone to the lateral nasal line. The authors also gauged the projection angle of the conchal bone and constitutional thickness of the inferior turbinate. RESULTS: After inferior turbinate outfracture, the shortest distance from the median line to the medial border of the conchal bone increased, and shortest distance from the medial border of the conchal bone to the lateral nasal line decreased. The projection angle decreased significantly by 6 months postoperatively. After outfracture, the thickness of the medial mucosa had increased significantly, wheras the thickness of the conchal bone had decreased significantly (p < 0.05). CONCLUSIONS: The effect of inferior turbinate outfracture is preserved for at least 6 months. Moreover, compensatory hypertrophy of the medial mucosa develops in the inferior turbinate after outfracture. Therefore, outfracture with medial submucosal volume reduction would be recommended as the best procedure for treating inferior turbinate hypertrophy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Redefining the Septal L-Strut to Prevent Collapse.

During septorhinoplasty, septal cartilage is frequently resected for various purposes but the L-strut is preserved. Numerous materials are inserted into the nasal dorsum during dorsal augmenation rhinoplasty without considering nasal structural safety. This study used a finite element method (FEM) to redefine the septal L-strut, to prevent collapse as pressure moved from the rhinion to the supratip breakpoint on the nasal dorsum and as the contact percentage between the caudal L-strut and the maxillary crest changed. We designed a 1-cm-wide L-strut model based on computed tomography data. At least 45% of the width of the L-strut in the inferior portion of the caudal strut must be preserved during septoplasty to stabilize the septum. In augmentation rhinoplasty, the caudal L-strut must either be preserved perfectly or reinforced to prevent collapse or distortion of the L-strut. The dorsal augmentation material must be fixed in an augmentation pocket to prevent movement of graft material toward the supratip breakpoint, which can disrupt the L-strut. We conducted a numerical analysis using a FEM to predict tissue/organ behavior and to help clinicians understand the reasons for target tissue/organ collapse and deformation.

Characteristics of Human Turbinate-Derived Mesenchymal Stem Cells Are Not Affected by Allergic Condition of Donor.

The characteristics of mesenchymal stem cells (MSCs) derived from human turbinates (hTMSCs) have not been investigated in allergic rhinitis. We evaluated the influence of allergic state of the donor on the characteristics, proliferation, and differentiation potential of hTMSCs, compared with hTMSCs derived from non-allergic patients. hTMSCs were isolated from five non-allergic and five allergic patients. The expression of toll-like receptors (TLRs) in hTMSCs was measured by FACS, and cell proliferation was measured using a cell counting kit. Cytokine secretion was analyzed using multiplex immunoassays. The osteogenic, chondrogenic, and adipogenic differentiation potentials of hTMSCs were evaluated by histology and gene expression analysis. In allergic patients, FACS analysis showed that TLR3 and TLR4 were more highly expressed on the surface of hTMSCs than TLR2 and TLR5. The proliferation of hTMSCs was not influenced by the presence of TLR priming. The expression of IL-6, IL-8, IL-12, IP-10, and RANTES was upregulated after the TLR4 priming. The differentiation potential of hTMSCs was not influenced by TLR priming. These characteristics of hTMSCs were similar to those of hTMSCs from non-allergic patients. We conclude that the allergic condition of the donor does not influence TLR expression, proliferation, or immunomodulatory potential of hTMSCs.

Redefining the septal L-strut in septal surgery.

In septal surgery, the surgeon preserves the L-strut, the portion anterior to a vertical line drawn from the rhinion to the anterior nasal spine (ANS) and at least a 1-cm width of the dorsal and caudal septal segment, to decrease the potential for loss of the tip and dorsal nasal support. However, nasal tip collapse and saddle deformities occur occasionally. We utilized a mechanical approach to determine the safe width size for the L-strut in contact with the maxillary crest. Five L-strut models were designed based on computed tomography data (80 patients) and previous studies (55 patients). All L-strut models connected the perpendicular plate of the ethmoid bone (PPE) and the maxillary crest and were assumed to be fixed to the PPE and maxillary crest. An approximated daily load was applied to the dorsal portion of the L-strut. Finite element analyses were performed to compare the stress, strain, and displacement distribution of all L-strut models. According to the differences in the contact area between the caudal L-strut and maxillary crest, there are significant differences in terms of the stress, strain, and displacement distribution in the L-strut. High stresses occurred at the inner corner of the L-strut when 60 - 100% of the strut was in contact with the maxillary crest. High stresses also occurred at the inferior portion of the caudal L-strut when 20 - 40% of the caudal strut was in contact with maxillary crest. We conclude that it is important to preserve the 1-cm width L-strut caudal segment, which corresponds to the portion posterior to a vertical line drawn from the rhinion to the ANS. In particular, we must maintain more than 40% of the contact area between the L-strut and the maxillary crest when the septal cartilage in the caudal portion of the L-strut is harvested.

Toll like receptor 3 & 4 responses of human turbinate derived mesenchymal stem cells: stimulation by double stranded RNA and lipopolysaccharide.

BACKGROUND AND OBJECTIVES: Multipotent mesenchymal stromal cells (MSCs) represent a promising cell-based therapy for a number of inflammatory or autoimmune diseases. Herein, Toll like receptor (TLR) expression by MSCs and their immune regulatory roles are investigated. In this study, we investigated the influence of TLR on the immune response, proliferation, and differentiation potential of human turbinated MSC (hTMSC) cultures in vitro. SUBJECTS AND METHODS: After isolating hTMSCs from discarded inferior turbinate tissue, FACS analysis was used to assess the expression of TLRs such as TLR2, TLR3, TLR4, and TLR5 in hTMSCs and cell proliferation was assessed using a cell counting kit (CCK)-8. Cytokine and chemokine secretions were analyzed with multiplex immunoassays for IL-1α, IL-1ß, IL-4, IL-6, IL-8, IL-10, IL-12, IP-10 (CXCL10), RANTES (CCL5), TNF-a, GM-CSF, and IFN-γ. The differentiation potential of hTMSCs was evaluated in the osteogenic, chondogenic, and adipogeinc media and analyzed by histology and gene expression related to differentiation. RESULTS: FACS analysis revealed that TLR3 and TLR4 expression consisted of a relatively high percentage of the surface proteins expressed by hTMSCs. The proliferation of hTMSCs was influenced and significantly increased by the presence of TLR4 agonists. In particular, hTMSCs produced a set of cytokines and chemokines and the expression of IL-6, IL-8, IL-12, IP-10 (CXCL10), RANTES (CCL5), TNF-α, and GM-CSF were up-regulated in response to the TLR4 agonist LPS. The osteogenic and adipogeinc differentiation potential of hTMSCs was not affected by TLR agonists. CONCLUSIONS: We conclude that TLR4 stimulation affects TLR expression, proliferation, and the immunomodulation potential of hTMSCs. Understanding the mechanism behind TLR's influence on hTMSCs and their immunomodulating properties would be useful for providing a novel target to exploit in the improvement of stem cell-based therapeutic strategies.

Characteristics of mesenchymal stem cells originating from the bilateral inferior turbinate in humans with nasal septal deviation.

BACKGROUND AND OBJECTIVES: Nasal septal deviation (NSD) is often associated with overgrowth of the unilateral inferior turbinate. In vivo and in vitro studies indicate that human mesenchymal stem cells (MSCs) are able to differentiate into multiple cell types, including osteoblasts. We tested the hypothesis that turbinate size affects human turbinate-derived MSC (hTMSCs) quantity, proliferation, and differentiation into osteogenic lineages, and that hypertrophic turbinates may predispose to NSD on the contralateral side. SUBJECTS AND METHODS: The hypertrophic and contralateral inferior turbinate tissues used in our study were obtained and cultured from the tissue discarded from 10 patients who underwent septoplasty and partial turbinectomy. After isolating the hTMSCs from both turbinates, the cells were enumerated using an automated cell counter. The expression of surface markers for MSCs over four passages was assessed by fluorescent-activated cell sorting analysis (FACS), and cell proliferation was assessed using a cell counting kit (CCK)-8 according to turbinate size. In addition, osteogenic differentiation of hTMSCs was identified using alkaline phosphatase (ALP) and alizarin red S staining, after which osteoblastic gene expression was evaluated. RESULTS: There was no significant difference in the number of hTMSCs. FACS analysis revealed that the hTMSCs were negative for CD14, CD19, CD34, and HLA-DR, and positive for CD29, CD73, and CD90, representing a characteristic MSC phenotype, with no significant difference between the two groups. The cellular proliferation and osteogenic differentiation potential of the hTMSCs were also not significantly different between the two groups. CONCLUSIONS: We conclude that turbinate size does not affect the characterization, proliferation, and osteogenic differentiation potential of hTMSCs in vitro test, and therefore should not affect the clinical decision of whether to use autologous or allogenic hTMSCs. However, more experiments are required to definitively state the relationship of hTMSCs with turbinate size or the process NSD in humans.

Age-related characteristics of multipotent human nasal inferior turbinate-derived mesenchymal stem cells.

BACKGROUND AND OBJECTIVES: Multipotent mesenchymal stem cells (MSCs) represent a promising cell-based therapy for a number of degenerative conditions. Understanding the effect of aging on MSCs is crucial for both autologous therapy development and allogenic donors in older subjects whom degenerative diseases typically afflict. In this study, we investigated the influence of donor age on the characteristics, proliferation, and differentiation potential of in vitro cultures of multipotent human turbinated mesenchymal stem cells (hTMSCs) from patients of various age groups. SUBJECTS AND METHODS: Twelve patients comprised the four age groups: (I) <20 years, (II) 20-39 years, (III) 40-59 years, and (IV) >60 years. Inferior turbinate tissues were discarded from patients undergoing partial turbinectomy. After isolating hTMSCs, the expression of the hTMSC surface markers CD14, CD19, CD34, CD73, CD90, CD105, and HLA-DR was assessed by FACS analysis, and cell proliferation was assessed using a cell counting kit (CCK)-8. The differentiation potential of hTMSCs was evaluated in osteogenic media by histology and determination of osteoblastic gene expression. RESULTS: FACS analysis revealed that hTMSCs were negative for CD14, CD19, CD34, and HLA-DR, and positive for CD73, CD90, and CD105, representing a characteristic MSC phenotype, and showed no significant differences among the age groups. Cellular proliferation and osteogenic differentiation potential of hTMSCs also showed no significant differences among the age groups. CONCLUSIONS: We conclude that donor age does not affect the characteristics, proliferation, and osteogenic differentiation potential of hTMSCs. Donor age may be excluded as a criterion in the guidelines for clinical use of the autologous or allogenic transplantation of hTMSCs.

Computationally robust and noise resistant numerical detector for the detection of atmospheric infrasound.

This work reports on a performance study of two numerical detectors that are particularly useful for infrasound arrays operating under windy conditions. The sum of squares of variance ratios (SSVR1)-proposed for detecting signals with frequency ranging from 1 to 10 Hz-is computed by taking the ratio of the squared sum of eigenvalues to the square of largest eigenvalue of the covariance matrix of the power spectrum. For signals with lower frequency between 0.015 and 0.1 Hz, SSVR2 is developed to reduce the detector's sensitivity to noise. The detectors' performances are graphically compared against the current method, the mean of cross correlation maxima (MCCM), using the receiver operating characteristics curves and three types of atmospheric infrasound, corrupted by Gaussian and Pink noise. The MCCM and SSVR2 detectors were also used to detect microbaroms from the 24 h-long infrasound data. It was found that the two detectors outperform the MCCM detector in both sensitivity and computational efficiency. For mine blasts corrupted by Pink noise (signal-to-noise ratio = -7 dB), the MCCM and SSVR1 detectors yield 62 and 88 % true positives when accepting 20% false positives. For an eight-sensor array, the speed gain is approximately eleven-fold for a 50 s long signal.

Anatomical analysis of nasal obstruction: nasal cavity of patients complaining of stuffy nose.

OBJECTIVES/HYPOTHESIS: To evaluate the relationship between subjective symptoms of nasal obstruction and the corresponding nasal anatomical parameters using paranasal computed tomography (PNS CT). STUDY DESIGN: Retrospective chart review at a tertiary referral center. METHODS: We studied 277 patients who underwent evaluation by the Nasal Obstruction Symptom Evaluation scale and a visual analogue scale of nasal obstruction for preoperative evaluation; 197 patients with nasal obstruction who underwent septoplasty were enrolled in the study group, and 80 patients without nasal septal deviation and without nasal obstruction who underwent a trans-sphenoidal pituitary tumor operation were enrolled in the control group. A preoperative coronal CT image was used to calculate both nasal cavity cross-sectional areas and the septal deviation angle at the three levels (internal nasal valve, ostiomeatal unit [OMU], and choana). RESULTS: Differences between the study group and the control group were found in all nasal anatomical parameters at the internal nasal valve, OMU, and choana. In the study group, subjective nasal obstruction symptoms were correlated with the septal deviation angle and the nasal cavity cross-sectional area at the OMU and the choana levels. However, there was no correlation between subjective symptoms of nasal obstruction and anatomical factors at the nasal valve level (P < .05). CONCLUSIONS: Coronal PNS CT revealed a relationship between subjective nasal obstructive symptoms and anatomical factors at the middle and posterior nasal levels, especially in patients complaining of stuffy nose. When septoplasty is performed, we must pay attention to correction of middle and posterior nasal septal deviation.

Efficacy of biodegradable synthetic polyurethane foam for packing nasal bone fractures.

BACKGROUND: Nasal bone fracture is the most common traumatic disease among facial bone fractures. General treatment of this trauma is closed reduction, followed by intranasal packing. Vaseline or Furacin roll gauze, and Merocel are commonly used packing materials, but the pain produced while removing the packing is fearful for the patients. To compensate for this shortcoming, there has been an increased use of biodegradable synthetic polyurethane foam (SPF) recently. We performed a retrospective review to analyze the effectiveness of SPF after the closed reduction of nasal bone fracture. PATIENTS AND METHODS: A retrospective review was conducted in 109 patients who underwent closed reduction for pure nasal bone fracture. One group was packed with Furacin roll gauze and the other was packed with SPF. Postoperative pain, hemostatic effect, supporting ability on the fractured segment, and healing of the injured nasal mucosa were compared between the 2 groups. RESULTS: A total of 109 patients were reviewed, with 61 patients packed with Furacin roll gauze (group A) and 48 patients packed with SPF (group B). Between the 2 groups, only visual analogue scale of pain at postoperative fourth day was statistically low in group B (P = 0.045) with other parameters showing no statistical difference. DISCUSSION: Nasal packing after closed reduction of nasal bone fractures support the reduced fractured bony segment and also has the main role on hemostasis and healing of mucosal injury. Removal of the packing is painful and fearful to the patients. SPF as nasal packing material provides superior outcome in terms of pain and satisfaction and, at the same time, is not inferior to the conventional packing materials with regard to bleeding control, mucosal wound healing, toxicity, and stability of reduced fracture segment.