Outcomes of SWI/SNF complex-deficient sinonasal carcinomas in a Southeast Asian cohort.

BACKGROUND: SWI/SNF complex-deficient sinonasal carcinomas are rare, genetically distinct, and aggressive entities. METHODS: SMARCB1 and SMARCA4 immunohistochemistry was retrospectively performed on a cohort of undifferentiated, poorly differentiated, and poorly defined sinonasal carcinomas. Survival outcomes were compared between SMARCB1/SMARCA4 (SWI/SNF complex)-deficient and -retained groups. RESULTS: Eight SWI/SNF complex-deficient (six SMARCB1-deficient, two SMARCA4-deficient) cases were identified among 47 patients over 12 years. Triple-modality treatment was more frequently utilized in SWI/SNF complex-deficient carcinomas than in SWI/SNF complex-retained carcinomas (71.4% vs. 11.8%, p = 0.001). After a median follow-up of 21.3 (IQR 9.9-56.0) months, SWI/SNF complex-deficient sinonasal carcinomas showed comparable recurrence rates (57.1% vs. 52.9%, p = 0.839), time-to-recurrence (7.3 [IQR 6.6-8.3] vs. 9.1 [IQR 3.9-17.4] months, p = 0.531), and overall survival (17.7 [IQR 11.8-67.0] vs. 21.6 [IQR 8.9-56.0] months, p = 0.835) compared to SWI/SNF complex-retained sinonasal carcinomas. CONCLUSION: Triple-modality treatment may improve survival in SWI/SNF complex-deficient sinonasal carcinomas.

Endoscopic and Radiologic Central Compartment Disease as Predictors of Perennial Inhalant Allergen Sensitization in Chronic Rhinosinusitis.

BACKGROUND: Central compartment atopic disease (CCAD) is a recently described variant of chronic rhinosinusitis (CRS) strongly associated with atopy. The association between central compartment disease (CCD) and inhalant allergy is not well established in South-East Asia, where perennial allergic rhinitis is common. OBJECTIVES: The primary objective was to evaluate endoscopic and radiologic CCD as predictors of perennial allergen sensitization in primary CRS. The secondary objective was to compare clinical characteristics of CCAD with other CRS subtypes (CRSwNP and CRSsNP). METHODS: A retrospective study of consecutive patients with primary CRS who underwent endoscopic sinus surgery at our institution was performed. Allergen sensitization was confirmed by skin or serum testing. Endoscopy records and computed tomography scans of paranasal sinuses were reviewed for CCD. The diagnostic accuracy of endoscopic and radiologic CCD in predicting atopy was calculated. RESULTS: There were 104 patients (43 CCAD, 30 CRSwNP and 31 CRSsNP). Endoscopic CCD was significantly associated with aeroallergen sensitization (odds ratio (OR) 3.99, 95% confidence interval (CI) 1.65-9.67, P = 0.002). Endoscopic CCD predicted atopy with 57% sensitivity, 72% specificity, 69% positive predictive value and positive likelihood ratio of 2.05. Radiologic CCD was not associated with aeroallergen sensitization (OR 0.728, 95%CI 0.292-1.82, P = 0.496). There were more CCAD patients who reported hyposmia (86% vs 42%, P < 0.001) and had anosmia on olfactory testing than CRSsNP (65% vs 14%, P = 0.015). The prevalence of atopy was significantly higher in CCAD than CRSwNP and CRSsNP (70% vs 37% and 42%, P = 0.015 and P = 0.05, respectively). Median serum total immunoglobulin E was higher in CCAD (283 IU/ml) and CRSwNP (127 IU/ml) than CRSsNP (27 IU/ml, P = 0.006 and P = 0.042, respectively). CONCLUSIONS: Endoscopic CCD was a better predictor of inhalant allergy than radiologic CCD in primary CRS, in a locale of perennial allergic rhinitis.

Radiopathologic predictors of 1- and 2-year frontal sinusotomy outcomes in a southeast Asian chronic rhinosinusitis population.

BACKGROUND: The frontal sinus and its drainage pathway are difficult spaces to navigate surgically. The complexity of the frontal recess anatomy as well as inflammatory factors may influence outcomes of endoscopic frontal sinusotomy. It is not clear which factors are more important in determining post-operative frontal ostium patency. OBJECTIVE: The objective is to investigate whether the distribution of fronto-ethmoidal cells, frontal recess dimensions and sinonasal inflammation predict frontal ostium patency at 1- and 2-years after endoscopic frontal sinusotomy. METHODS: A retrospective review of 94 chronic rhinosinusitis patients (185 sides) who had undergone endoscopic frontal sinusotomies between 2015 and 2019 was conducted. Computed tomography was used to evaluate the type of fronto-ethmoidal cells present and determine the dimensions of the frontal recess. The International Classification of the Radiological Complexity of frontal recess and frontal sinus was used to grade the complexity of frontal recess anatomy. Mucosal inflammation was graded according to a structured histopathology report. Frontal ostium patency at 1- and 2-years post-operatively was recorded. RESULTS: The frontal ostium patency rates were 80.9% and 73.4% at 1- and 2-years respectively. Eosinophilic predominance (adjusted OR 3.5, 95% CI 1.6-8.0, p = 0.003) and mucosal ulceration on histology (adjusted OR 4.5, 95% CI 1.1-17.9, p = 0.033) predicted ostial stenosis at 1 year. Smoking (adjusted OR 7.6, 95% CI 2.4-24.7, p = 0.001), aspirin exacerbated respiratory disease (AERD) (adjusted OR 7.6, 95% CI 1.9-30.1, p = 0.004) and histological findings of severe inflammation (adjusted OR 8.9, 95% CI 1.9-41.2, p = 0.005) were independent predictors of ostial stenosis at 2 years. Frontal cell patterns, frontal recess dimensions and frontal recess complexity did not predict frontal ostium stenosis at both 1- and 2-years post-operatively. CONCLUSION: Post-operative control of sinonasal inflammation is important in maintaining frontal ostium patency, regardless of frontal cell patterns or frontal recess dimensions.

Deconstructive versus reconstructive approach to internal carotid artery blowout in radiated nasopharyngeal carcinoma: A tertiary center experience and systematic review.

The objective of this study was to compare the outcomes of parent artery occlusion (PAO) versus stent-assisted reconstruction in radiated nasopharyngeal carcinoma (NPC) patients with internal carotid artery (ICA) blowouts. A retrospective review from our institution (2011-2021) and systematic review of Pubmed and Embase (1995-2022) was performed. Twenty-eight eligible studies were identified. Eighty-six PAOs and 37 stent-assisted reconstructions were analyzed, including 11 PAOs and 5 stents from our institution. Stents were associated with significantly higher incidence of overall re-bleeding (16.2% [95% CI 7.4-31.9] vs. 4.6% [95% CI 1.3-13.5], p = 0.047), delayed stroke (5.4% [95% CI 1.3-19.4] vs. 0%, p = 0.034) and reduced median survival (7.1 [95% CI 3.8-14.0] months vs. 29.0 [95% CI 9.4-63.4] months, p = 0.017) compared to PAO. There were no significant differences in terms of overall stroke, infection, extruded/migrated foreign body, and peri-procedure death. PAO is preferred over reconstructive treatment in patients with adequate collateral circulation.

Endovascular embolisation of external carotid artery system haemorrhage in radiated nasopharyngeal carcinoma.

PURPOSE: To review the effectiveness and safety of embolisation in managing haemorrhage from the external carotid artery (ECA) system in radiated nasopharyngeal carcinoma (NPC) patients. METHODS: Radiated NPC patients who presented with severe oronasal bleeding and underwent digital subtraction angiography that excluded blowouts from the internal carotid artery from 2011 to 2021 were reviewed. Those who subsequently underwent embolisation of the ECA system were analysed for technical success rate, post-embolisation re-bleeding rate and complications. RESULTS: Seventeen embolisations were performed in fifteen patients during the 10-year period. The technical success rate was 100%, however the early haemostatic rate (no re-bleed within 7 days of embolisation) was 70.6% (12/17) and the overall long-term haemostatic rate was 58.8% (10/17). The re-bleed rates of targeted and empiric embolisations were 33.3% (3/9) and 50.0% (4/8), respectively. The re-bleed rates with liquid agents, coils and particles were 0% (0/7), 33.3% (1/3) and 85.7% (6/7), respectively. Amongst the embolisations utilising liquid agents, 71.4% (5/7) were targeted, distal embolisations. All re-bleeds underwent surgical ligation or repeat embolisation; half of them further experienced recurrent bleeding. There were no significant complications with embolisation. CONCLUSION: Although embolisation of the ECA system in NPC has a high technical success rate and is safe, re-bleeding appears to be common. Targeted, distal embolisation with liquid embolics appear to have good haemostatic effect. Clinicians should be aware that patients may need repeated procedures to secure haemostasis.

Transcriptomics of rhinovirus persistence reveals sustained expression of RIG-I and interferon-stimulated genes in nasal epithelial cells in vitro.

BACKGROUND: Human rhinoviruses (HRVs) are frequently associated with asthma exacerbations, and have been found in the airways of asthmatic patients. While HRV-induced acute infection is well-documented, it is less clear whether the nasal epithelium sustains prolonged HRV infections along with the associated activation of host immune responses. OBJECTIVE: To investigate sustainably regulated host responses of human nasal epithelial cells (hNECs) during HRV persistence. METHODS: Using a time-course study, HRV16 persistence and viral replication dynamics were established using an in vitro infection model of hNECs. RNA sequencing was performed on hNECs in the early and late stages of infection at 3 and 14 days post-infection (dpi), respectively. The functional enrichment of differentially expressed genes (DEGs) was evaluated using gene ontology (GO) and Ingenuity pathway analysis. RESULTS: HRV RNA and protein expression persisted throughout prolonged infections, even after decreased production of infectious virus progeny. GO analysis of unique DEGs indicated altered regulation of pathways related to ciliary function and airway remodeling at 3 dpi and serine-type endopeptidase activity at 14 dpi. The functional enrichment of shared DEGs between the two time-points was related to interferon (IFN) and cytoplasmic pattern recognition receptor (PRR) signaling pathways. Validation of the sustained regulation of candidate genes confirmed the persistent expression of RIG-I and revealed its close co-regulation with interferon-stimulated genes (ISGs) during HRV persistence. CONCLUSIONS: The persistence of HRV RNA does not necessarily indicate an active infection during prolonged infection. The sustained expression of RIG-I and ISGs in response to viral RNA persistence highlights the importance of assessing how immune-activating host factors can change during active HRV infection and the immune regulation that persists thereafter.

Human Nasal Epithelial Cells Sustain Persistent SARS-CoV-2 Infection In Vitro, despite Eliciting a Prolonged Antiviral Response.

The dynamics of SARS-CoV-2 infection in COVID-19 patients are highly variable, with a subset of patients demonstrating prolonged virus shedding, which poses a significant challenge for disease management and transmission control. In this study, the long-term dynamics of SARS-CoV-2 infection were investigated using a human well-differentiated nasal epithelial cell (NEC) model of infection. NECs were observed to release SARS-CoV-2 virus onto the apical surface for up to 28 days postinfection (dpi), further corroborated by viral antigen staining. Single-cell transcriptome sequencing (sc-seq) was utilized to explore the host response from infected NECs after short-term (3-dpi) and long-term (28-dpi) infection. We identified a unique population of cells harboring high viral loads present at both 3 and 28 dpi, characterized by expression of cell stress-related genes DDIT3 and ATF3 and enriched for genes involved in tumor necrosis factor alpha (TNF-α) signaling and apoptosis. Remarkably, this sc-seq analysis revealed an antiviral gene signature within all NEC cell types even at 28 dpi. We demonstrate increased replication of basal cells, absence of widespread cell death within the epithelial monolayer, and the ability of SARS-CoV-2 to replicate despite a continuous interferon response as factors likely contributing to SARS-CoV-2 persistence. This study provides a model system for development of therapeutics aimed at improving viral clearance in immunocompromised patients and implies a crucial role for immune cells in mediating viral clearance from infected epithelia. IMPORTANCE Increasing medical attention has been drawn to the persistence of symptoms (long-COVID syndrome) or live virus shedding from subsets of COVID-19 patients weeks to months after the initial onset of symptoms. In vitro approaches to model viral or symptom persistence are needed to fully dissect the complex and likely varied mechanisms underlying these clinical observations. We show that in vitro differentiated human NECs are persistently infected with SARS-CoV-2 for up to 28 dpi. This viral replication occurred despite the presence of an antiviral gene signature across all NEC cell types even at 28 dpi. This indicates that epithelial cell intrinsic antiviral responses are insufficient for the clearance of SARS-CoV-2, implying an essential role for tissue-resident and infiltrating immune cells for eventual viral clearance from infected airway tissue in COVID-19 patients.

Precision Medicine in Chronic Rhinosinusitis: Where Does Allergy Fit In?

Chronic rhinosinusitis (CRS) is a clinical syndrome stemming from persistent inflammation of the sinonasal mucosa. Phenotypically, it is traditionally and widely described according to the presence or absence of polyps. While this distinction is simple to use, it has little bearing on prognosis and treatment, for CRS is essentially an inflammatory disease resulting from dysregulated interaction between a multitude of host and environmental factors. Allergy is merely one of them and, like many of the proposed aetiologies, has been subject to much debate which will be discussed here. As our understanding of CRS continues to evolve, previous so-called conventional wisdom about phenotypes (e.g. CRS with nasal polyps is associated with Type 2 inflammation) is being challenged, and new phenotypes are also emerging. In addition, there is growing interest in defining the endotypes of CRS to deliver precise and personalised treatment, especially pertaining to the development of biologics for the group of severe, difficult-to-treat CRS patients. A proposed model of precision medicine tailored to management of CRS will also be introduced to readers, which can be continually modified to adapt to new discoveries about this exciting condition.

Clinical predictors of internal carotid artery blowout in patients with radiated nasopharyngeal carcinoma.

BACKGROUND: The primary objective is to identify clinical predictors of internal carotid artery (ICA) blowout in radiated nasopharyngeal carcinoma (NPC). METHODS: Seventeen ICA blowouts, 14 external carotid artery (ECA) bleeds, and 60 controls were identified from January 1, 2007 to July 31, 2020. Multinomial logistic regression was performed to identify features predictive of ICA blowouts. RESULTS: Headache was significantly more common among ICA blowouts than ECA bleeds and controls (58.8% vs. 7.1% vs. 6.7%, p < 0.001). The petrous skull base and sphenoid sinus lateral wall was eroded in all petrous and cavernous segment blowouts, respectively. Nasoendoscopy showing exposed clivus (OR 20.5, 95%CI 1.3-324.2) and computed tomography demonstrating skull base erosion (OR 17.8, 95%CI 1.0-311.0) were significantly associated with ICA blowouts compared to controls. CONCLUSIONS: Findings of headache and skull base erosion on nasoendoscopy or imaging during NPC surveillance warrants prophylactic intervention to avoid an ICA blowout.

Induction of IL-25 Expression in Human Nasal Polyp Epithelium by Influenza Virus Infection is Abated by Interferon-Alpha Pretreatment.

BACKGROUND: Epithelial cytokines including IL-25, IL-33 and thymic stromal lymphopoietin (TLSP) are recently established as drivers of type 2 chronic inflammatory diseases such as chronic rhinosinusitis with nasal polyps (CRSwNP). Here, we further confirmed the increased expression of IL-25 in CRSwNP and investigated potential contributors of IL-25 in CRSwNP epithelium. METHODS: Sixty CRSwNP, 25 CRSsNP and 15 healthy control tissues were examined for IL-25 expression and for the accompanying type 2 inflammatory cytokines. We then tested different respiratory virus infections on human nasal epithelial cells (hNECs) for their ability to trigger IL-25 expression. In addition, we subjected hNECs generated from CRSwNP tissues to pretreatment with recombinant interferon-alpha (IFN-α) prior to viral infection to evaluate IFN effects on IL-25 induction. RESULTS: We confirmed that significantly enhanced levels of IL-25 were observed in CRSwNP tissues, and that IL-25 expression correlated with type 2 inflammatory cytokine expression. In vitro, we observed significantly elevated IL-25 in hNECs infected with influenza A virus as early as 24 hours post-infection (hpi), regardless of tissue origin, and IL-25 correlated positively with viral load. While other respiratory viruses exhibited increasing trends of IL-25, these were not significant at the time-points tested. IFN-α treatment of CRSwNP epithelium was found to exert bimodal effects, ie IFN-α treatment alone induced moderate IL-25 expression, whereas IFN-α pretreatment of hNECs before influenza infection significantly diminished IL-25 induction by active influenza virus infection. CONCLUSION: We have authenticated the observation of elevated IL-25 in CRSwNP, which is correlated with type 2 inflammatory cytokines. Notably, we identified influenza virus infection as a potential contributor of IL-25 in both control and CRSwNP epithelium during active infection. This IL-25 induction can be abated by IFN-α pretreatment which ameliorated active influenza infection. TRIAL REGISTRATION: Chictr.org.cn ChiCTR-BON-16010179, Registered 18 December 2016, http://www.chictr.org.cn/showproj.aspx?proj=17331. The authors agree on the sharing of deidentified participant data where it pertains to request directly related to the data in this article when contacted (Haiyu Hong; honghy@mail.sysu.edu.cn).

Mucus composition abnormalities in sinonasal mucosa of chronic rhinosinusitis with and without nasal polyps.

Mucus secretion and its composition are vital in the maintenance of airway health, among which hypoxia-inducible factors (HIFs) are thought to be involved in the regulation of mucin synthesis and regulation. Nasal mucus composition difference between healthy individuals and chronic rhinosinusitis (CRS) patients may contribute to the pathology of chronic nasal diseases, but so far, their role has yet to be completely understood. Nasal biopsy specimens were obtained from 24 healthy subjects and 99 patients with CRS without (CRSsNP, n=36) or with (CRSwNP, n=63) nasal polyps. Immunohistochemical (IHC) and immunofluorescent (IF) staining, quantitative real-time PCR, and western blot were performed to compare the nasal mucus composition between the subjects. Areas of the serous gland and mucous gland were both significantly increased in CRSsNP patients. In CRSwNP patients, a decrease in submucosal gland density and a marked increase in goblet cells were observed. The major gel-forming mucins in the sinonasal mucosa of CRSsNP and CRSwNP are MUC5B and MUC5AC respectively. Mucous cells are found in a higher proportion in both CRSsNP and CRSwNP. The proportion of MUC5AC-positive goblet cells was increased in CRSwNP. The mRNA level of HIF-2α was significantly increased in CRS, and both HIF-1α and HIF-2α were expressed in serous cell but not mucous cell. Over secretion and altered composition of mucus are observed in sinonasal mucosa of CRS, which was mainly associated with glandular hyperplasia in CRSsNP and goblet cell hyperplasia in CRSwNP. Mucus abnormality compromised both non-specific and specific antimicrobial capabilities in the sinonasal mucosa. HIF expression may contribute to differences in mucin synthesis and serous gland regulation, which needs further investigation to understand the pathology of CRS.

Contact-Free Co-Culture Model for the Study of Innate Immune Cell Activation During Respiratory Virus Infection.

The early interactions between the nasal epithelial layer and the innate immune cells during viral infections remains an under-explored area. The significance of innate immunity signaling in viral infections has increased substantially as patients with respiratory infections who exhibit high innate T cell activation show a better disease outcome. Hence, dissecting these early innate immune interactions allows the elucidation of the processes that govern them and may facilitate the development of potential therapeutic targets and strategies for dampening or even preventing early progression of viral infections. This protocol details a versatile model that can be used to study early crosstalk, interactions, and activation of innate immune cells from factors secreted by virally infected airway epithelial cells. Using an H3N2 influenza virus (A/Aichi/2/1968) as the representative virus model, innate cell activation of co-cultured peripheral blood mononuclear cells (PBMCs) has been analyzed using flow cytometry to investigate the subsets of cells that are activated by the soluble factors released from the epithelium in response to the viral infection. The results demonstrate the gating strategy for differentiating the subsets of cells and reveal the clear differences between the activated populations of PBMCs and their crosstalk with the control and infected epithelium. The activated subsets can then be further analyzed to determine their functions as well as molecular changes specific to the cells. Findings from such a crosstalk investigation may uncover factors that are important for the activation of vital innate cell populations, which are beneficial in controlling and suppressing the progression of viral infection. Furthermore, these factors can be universally applied to different viral diseases, especially to newly emerging viruses, to dampen the impact of such viruses when they first circulate in naïve human populations.

Magnetic Resonance Imaging Study of the Pericranial Flap and Its Local Effects Following Endoscopic Craniofacial Resection.

OBJECTIVES/HYPOTHESIS: To describe the magnetic resonance imaging (MRI) characteristics of the pericranial flap, changes in the pericranial flap thickness over time, presence of frontal sinus opacification, and presence of frontal lobe herniation into the nasal cavity. STUDY DESIGN: Retrospective case series. METHODS: Seventeen consecutive endoscopic craniofacial resections with pericranial flap reconstruction performed at a tertiary hospital from 2010 to 2019 were reviewed. Sixty-eight serial MRI scans were evaluated. RESULTS: All pericranial flaps consistently featured a homogenous appearance on T1-weighted sequence and enhanced with contrast. On T2-weighted sequence, the skull base reconstruction demonstrated four layers of alternating hypo- and hyperintensity, which corresponded with the inlay synthetic graft or neodura (hypointense), loose areolar tissue (hyperintense), fibrous pericranium (hypointense), and nasal mucosa or granulation tissue (hyperintense). The mean pericranial flap thickness was 9.9 mm. In thicker flaps, the loose areolar layer contributed the bulk of the thickness. Of 13 patients who underwent three or more serial MRI scans, 11 flaps (84.6%) were stable and two (15.4%) had >50% reduction in their original thickness over time. Thirteen of 17 (76.5%) patients had frontal sinus opacification on follow-up. None developed frontal sinus mucoceles or frontal lobe herniation. CONCLUSIONS: The pericranial flap has a distinctive MRI appearance, especially on T2-weighted sequence. The thickness of the flap remains relatively stable over time for most patients even following radiotherapy. It is a sturdy flap that is able to support the frontal lobe. Frontal sinus obstruction is common, although complications from this appear to be rare. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E90-E97, 2021.

Next-Generation Allergic Rhinitis Care in Singapore: 2019 ARIA Care Pathways.

Allergic rhinitis (AR) is prevalent in Singapore, with a significant disease burden. Afflicting up to 13% of the population, AR impairs quality of life, leads to reduced work productivity and is an independent risk factor for asthma. In the last 2 decades, local studies have identified patient and physician behaviours leading to suboptimal control of the disease. Yet, there is an overall lack of attention to address this important health issue. Allergic Rhinitis and its Impact on Asthma (ARIA) is a European organisation aimed at implementing evidence-based management for AR worldwide. Recent focus in Europe has been directed towards empowering patients for self-management, exploring the complementary role of mobile health, and establishing healthcare system-based integrated care pathways. Consolidation of these ongoing efforts has led to the release of the 2019 ARIA care pathways. This review summarises the ARIA update with particular emphasis on the current status of adult AR in Singapore. In addition, we identify unmet needs and future opportunities for research and clinical care of AR in the local context.

Infection of human Nasal Epithelial Cells with SARS-CoV-2 and a 382-nt deletion isolate lacking ORF8 reveals similar viral kinetics and host transcriptional profiles.

The novel coronavirus SARS-CoV-2 is the causative agent of Coronavirus Disease 2019 (COVID-19), a global healthcare and economic catastrophe. Understanding of the host immune response to SARS-CoV-2 is still in its infancy. A 382-nt deletion strain lacking ORF8 (Δ382 herein) was isolated in Singapore in March 2020. Infection with Δ382 was associated with less severe disease in patients, compared to infection with wild-type SARS-CoV-2. Here, we established Nasal Epithelial cells (NECs) differentiated from healthy nasal-tissue derived stem cells as a suitable model for the ex-vivo study of SARS-CoV-2 mediated pathogenesis. Infection of NECs with either SARS-CoV-2 or Δ382 resulted in virus particles released exclusively from the apical side, with similar replication kinetics. Screening of a panel of 49 cytokines for basolateral secretion from infected NECs identified CXCL10 as the only cytokine significantly induced upon infection, at comparable levels in both wild-type and Δ382 infected cells. Transcriptome analysis revealed the temporal up-regulation of distinct gene subsets during infection, with anti-viral signaling pathways only detected at late time-points (72 hours post-infection, hpi). This immune response to SARS-CoV-2 was significantly attenuated when compared to infection with an influenza strain, H3N2, which elicited an inflammatory response within 8 hpi, and a greater magnitude of anti-viral gene up-regulation at late time-points. Remarkably, Δ382 induced a host transcriptional response nearly identical to that of wild-type SARS-CoV-2 at every post-infection time-point examined. In accordance with previous results, Δ382 infected cells showed an absence of transcripts mapping to ORF8, and conserved expression of other SARS-CoV-2 genes. Our findings shed light on the airway epithelial response to SARS-CoV-2 infection, and demonstrate a non-essential role for ORF8 in modulating host gene expression and cytokine production from infected cells.

Role of adjunctive treatment strategies in COVID-19 and a review of international and national clinical guidelines.

The coronavirus disease (COVID-19) pandemic has led to a global struggle to cope with the sheer numbers of infected persons, many of whom require intensive care support or eventually succumb to the illness. The outbreak is managed by a combination of disease containment via public health measures and supportive care for those who are affected. To date, there is no specific anti-COVID-19 treatment. However, the urgency to identify treatments that could turn the tide has led to the emergence of several investigational drugs as potential candidates to improve outcome, especially in the severe to critically ill. While many of these adjunctive drugs are being investigated in clinical trials, professional bodies have attempted to clarify the setting where the use of these drugs may be considered as off-label or compassionate use. This review summarizes the clinical evidence of investigational adjunctive treatments used in COVID-19 patients as well as the recommendations of their use from guidelines issued by international and national organizations in healthcare.

An endoscopic anatomical study of the levator veli palatini and its relationship to the parapharyngeal internal carotid artery.

BACKGROUND: The objectives of this study are to describe the levator veli palatini (LVP) as a landmark for the parapharyngeal internal carotid artery (pICA) and the endoscopic course of the pICA. METHODS: Cadaver dissection and illustrative case study. RESULTS: Seven cadaveric heads (12 sides) were dissected. In all 12 sides, the LVP was consistently located between the Eustachian tube and the pICA near the skull base, making the LVP just anterior to and the closest structure to the pICA. The distance between the pICA and the nares ranged from 9.0 to 12.7 cm. The distance between the pICA and the midpoint of the nasopharynx ranged from 1.9 to 3.7 cm. The case study illustrated the applicability of these findings. CONCLUSION: The LVP is a reliable and precise landmark for the pICA. A safe working distance to the pICA is 1.9 cm from the midpoint of the nasopharynx and 9.0 cm from the nares.

Host Antiviral Response Suppresses Ciliogenesis and Motile Ciliary Functions in the Nasal Epithelium.

BACKGROUND: Respiratory viral infections are one of the main drivers of development and exacerbation for chronic airway inflammatory diseases. Increased viral susceptibility and impaired mucociliary clearance are often associated with chronic airway inflammatory diseases and served as risk factors of exacerbations. However, the links between viral susceptibility, viral clearance, and impaired mucociliary functions are unclear. Therefore, the objective of this study is to provide the insights into the effects of improper clearance of respiratory viruses from the epithelium following infection, and their resulting persistent activation of antiviral response, on mucociliary functions. METHODS: In order to investigate the effects of persistent antiviral responses triggered by viral components from improper clearance on cilia formation and function, we established an in vitro air-liquid interface (ALI) culture of human nasal epithelial cells (hNECs) and used Poly(I:C) as a surrogate of viral components to simulate their effects toward re-epithelization and mucociliary functions of the nasal epithelium following damages from a viral infection. RESULTS: Through previous and current viral infection expression data, we found that respiratory viral infection of hNECs downregulated motile cilia gene expression. We then further tested the effects of antiviral response activation on the differentiation of hNECs using Poly(I:C) stimulation on differentiating human nasal epithelial stem/progenitor cells (hNESPCs). Using this model, we observed reduced ciliated cell differentiation compared to goblet cells, reduced protein and mRNA in ciliogenesis-associated markers, and increased mis-assembly and mis-localization of ciliary protein DNAH5 following treatment with 25 µg/ml Poly(I:C) in differentiating hNECs. Additionally, the cilia length and ciliary beat frequency (CBF) were also decreased, which suggest impairment of ciliary function as well. CONCLUSION: Our results suggest that the impairments of ciliogenesis and ciliary function in hNECs may be triggered by specific expression of host antiviral response genes during re-epithelization of the nasal epithelium following viral infection. This event may in turn drive the development and exacerbation of chronic airway inflammatory diseases.

Novel findings in immunopathophysiology of chronic rhinosinusitis and their role in a model of precision medicine.

Our understanding of the pathophysiology of chronic rhinosinusitis (CRS) is continuously evolving. The traditional description of CRS in terms of two phenotypes based on the presence or absence of nasal polyps belies the underlying intricate immunopathophysiological processes responsible for this condition. CRS is being increasingly recognized as a disease spectrum encompassing a range of inflammatory states in the sinonasal cavity, with non-type 2 inflammatory disease on one end, type 2 inflammatory, eosinophil-heavy disease on the other and an overlap of both in different proportions in between. Abundance in research on the immune mechanisms of CRS has revealed various new endotypes that hold promise as biomarkers for the development of targeted therapies in severe, uncontrolled CRS. The introduction of precision medicine to manage this chronic, complex condition is a step forward in providing individualized care for all patients with CRS. In this review, the latest research on the pathophysiology of CRS with a focus on potential novel biomarkers and treatment options over the last 2 years are summarized and integrated into a suggested model of precision medicine in CRS.

An Integrated Analysis of Radial Spoke Head and Outer Dynein Arm Protein Defects and Ciliogenesis Abnormality in Nasal Polyps.

Background: Nasal polyp (NP) is a chronic upper airway inflammatory disease that is frequently triggered by defective host-defense. However, the mechanisms underlying the impaired barrier function such as cilia-mediated mucociliary clearance remain poorly understood. Objective: To assess ciliary ultrastructural and ciliogenesis marker expression and the phenotypes of ciliated cells in NP. Methods: NP biopsy samples were obtained from 97 NP patients and inferior turbinate from 32 healthy controls. Immunofluorescence staining, quantitative polymerase chain reaction, and single-cell cytospin staining were performed. We classified the patterns of radial spoke head protein (RSPH) 1, 4A (RSPH4A), 9 (RSPH9), and dynein axonemal heavy chain 5 (DNAH5) localization. A semi-quantitative scoring system was developed to assess their expression patterns and associations with ciliogenesis markers [centrosomal protein 110 (CP110) and forkhead box j1 (FOXJ1)]. Results: Median scores of RSPH1, RSPH4A, RSPH9, and DNAH5 were significantly higher in NP than in healthy controls, particularly in eosinophilic NPs. Expression pattern scores of RSPH1, RSPH4A, RSPH9, and DNAH5 correlated positively with each other in both groups. In primary-cell specimens, abnormal expression patterns were significantly more common in NP. The total fluorescence intensity of CP110 and FOXJ1 was significantly higher in NPs and correlated positively with expression pattern scores of RSPH1, RSPH4A, RSPH9, and DNAH5. A trend towards lengthened cilia was observed in NP. Conclusion: In the chronic airway inflammatory milieu, the up-regulated ciliogenesis correlates with the abnormal expression of ciliary ultrastructural markers (i.e., DNAH5) in NP (particularly eosinophilic NP).