Noncanonical NF-kappaB activation requires coordinated assembly of a regulatory complex of the adaptors cIAP1, cIAP2, TRAF2 and TRAF3 and the kinase NIK.

Recent studies suggest that nuclear factor kappaB-inducing kinase (NIK) is suppressed through constitutive proteasome-mediated degradation regulated by TRAF2, TRAF3 and cIAP1 or cIAP2. Here we demonstrated that the degradation of NIK occurs upon assembly of a regulatory complex through TRAF3 recruitment of NIK and TRAF2 recruitment of cIAP1 and cIAP2. In contrast to TRAF2 and TRAF3, cIAP1 and cIAP2 seem to play redundant roles in the degradation of NIK, as inhibition of both cIAPs was required for noncanonical NF-kappaB activation and increased survival and proliferation of primary B lymphocytes. Furthermore, the lethality of TRAF3 deficiency in mice could be rescued by a single NIK gene, highlighting the importance of tightly regulated NIK.

A Rare Case of Laryngeal Non-IgM Lymphoplasmacytic Lymphoma.

Laryngeal lymphoplasmacytic lymphoma has been previously reported only a handful of times in the literature. It can be difficult to diagnose without significant histologic workup and proper methodology. Here, we demonstrate the first known case of laryngeal lymphoplasmacytic lymphoma with non-immunoglobulin M (IgM) features. In this case report, a 79-year-old female with seropositive rheumatoid arthritis presented with five months of dysphonia and dyspnea on exertion. Lab studies revealed high levels of serum IgA and IgG. Flexible laryngoscopy and computed tomography of the neck showed a left supraglottic submucosal mass, which was surgically excised with a carbon dioxide laser. The histology of the mass confirmed the diagnosis of lymphoplasmacytic lymphoma. The patient was treated with 30.6 Gy of radiation therapy and eight cycles of rituximab with successful remission of her lymphoma and no evidence of disease recurrence six months after treatment completion. Lymphoplasmacytic lymphoma without corresponding IgM gammopathy is unusual and has been shown to have a higher frequency of extramedullary involvement. This is the first known manifestation of non-IgM lymphoplasmacytic lymphoma in the larynx.

Secondary syphilis of the oropharynx and cervical lymph nodes: a case report.

Secondary syphilis rarely affects the head and neck including the oropharynx and cervical lymph nodes. These patients present with throat pain, cystic/necrotic lymphadenopathy, and mucosal swelling. Sometimes this constellation of symptoms can be mistaken for head and neck cancer. We report a case of an enlarging throat and painless cystic neck mass in a transgender woman in her forties who was initially suspected to have oropharyngeal squamous cell carcinoma. A subsequent workup revealed the presence of spirochetes without cellular atypia consistent with secondary syphilis. We include the ultrasonography images as well as an endoscopic photograph of the oropharyngeal manifestation in this report.

Adverse Events in Hypoglossal Nerve Stimulator Implantation: 5-Year Analysis of the FDA MAUDE Database.

OBJECTIVE: Use of hypoglossal nerve stimulator implantation has dramatically improved the surgical treatment of multilevel airway collapse during obstructive sleep apnea (OSA). Understanding causes of adverse events and their impact on patients undergoing stimulator implantation will help improve patient preparation and surgical practices to avoid future complications. STUDY DESIGN: This study is a retrospective review of the US Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database, a publicly available voluntary reporting system. SETTING: National patient event database. METHODS: The MAUDE database was searched for reports associated with the terms "hypoglossal nerve stimulator" and "Inspire," being the only currently FDA-approved system for upper airway stimulation for OSA. All records were searched with the events limited in dates between May 2014 and September 2019. RESULTS: A total of 132 patient reports were identified over the 5-year inclusion period, containing 134 adverse events. The reported adverse events resulted in 32 device revision procedures as well as 17 explantations. Device migration and infection were 2 of the most commonly reported adverse events. Complications not witnessed in previous large-scale clinical trials included pneumothorax, pleural effusion, and lead migration into the pleural space. CONCLUSION: Previous data have demonstrated hypoglossal nerve stimulator implantation results in reliable OSA improvement. However, a number of technical difficulties and complications still exist during the perioperative period, which should be communicated to patients during the surgical consent process.

Tracheostomy Considerations during the COVID-19 Pandemic.

OBJECTIVE: To compile current best practices regarding tracheostomy decision making, care, and technical performance during the global COVID-19 pandemic. DATA SOURCES: Articles listed in PubMed and Google sources for up-to-date information. REVIEW METHODS: All sources presenting objective evidence related to the topic were reviewed and distilled. CONCLUSIONS: Tracheostomy in patients with coronavirus disease should be a rare event yet one that requires significant decision making and procedural deliberation. Indications for surgery must be balanced by risk of disease transmission to health care workers. Considerations are given to personal protective equipment, viral testing, and alternatives. IMPLICATIONS FOR PRACTICE: Otolaryngologists worldwide must be aware of these considerations to provide safe patient care without undue risk to themselves or their hospital coworkers.

Management of exposed total knee prostheses with microvascular tissue transfer.

INTRODUCTION: Exposure of a knee endoprosthesis represents a limb-threatening condition, requiring long-term antibiosis, irrigation, and serial debridement to avoid knee arthrodesis or amputation. Although traditional orthopedic surgical doctrine mandates removal of exposed hardware under a dehisced wound, salvage of exposed prostheses using local muscle flap coverage has been reported. However, the complex three-dimensional geometry of the soft tissue surrounding the knee as well as the requirement for sustained local tissue levels of antibiotics to re-sterilize the hardware suggest that microvascular tissue transfer may constitute an advantageous means of wound coverage, increasing both limb and prosthesis salvage rates. We report our experience with free tissue transfer reconstruction of these complex wounds. METHODS: We treated 11 complex wounds with exposed total knee arthroplasty prostheses with free tissue transfer. Three of 11 patients had failed previous local muscular rotation flap coverage. Five latissimus dorsi muscle flaps and 6 rectus abdominis muscle flaps were used in our series. Wounds were closed after aggressive surgical debridement, antibiotic irrigation, and intravenous antibiosis. RESULTS: Eleven of 11 free flaps were successful (100%), and we achieved limb salvage in 11/11 limbs (100%) and prosthesis salvage in 10/11 knees (91%), with one prosthesis removed at an outside facility followed by knee arthrodesis. CONCLUSION: The advantages of microvascular tissue transfer are well suited to the treatment of exposed knee endoprostheses. The reliable rectus and latissimus flaps provide robust local perfusion to the wound, fill complex three-dimensional contour defects around knee implants, and lead to a high rate of salvage of both limbs and prostheses.

Adipose-Derived Mesenchymal Stromal Cells Persist in Tissue-Engineered Vocal Fold Replacement in Rabbits.

OBJECTIVES:: Cell therapies using mesenchymal stromal cells (MSCs) have been proposed as a promising new tool for the treatment of vocal fold scarring. However, the mechanisms by which MSCs promote healing as well as their duration of survival within the host vocal fold have yet to be defined. The aim of this work was to assess the persistence of embedded MSCs within a tissue-engineered vocal fold mucosal replacement in a rabbit model of vocal fold injury. METHODS:: Male rabbit adipose-derived MSCs were embedded within a 3-dimensional fibrin gel, forming the cell-based outer vocal fold replacement. Four female rabbits underwent unilateral resection of vocal fold epithelium and lamina propria and reconstruction with cell-based outer vocal fold replacement implantation. Polymerase chain reaction and fluorescent in situ hybridization for the sex-determining region of the Y chromosome (SRY-II) in the sex-mismatched donor-recipient pairs sought persistent cells after 4 weeks. RESULTS:: A subset of implanted male cells was detected in the implant site at 4 weeks. Many SRY-II-negative cells were also detected at the implant site, presumably representing native female cells that migrated to the area. No SRY-II signal was detected in contralateral control vocal folds. CONCLUSIONS:: The emergent tissue after implantation of a tissue-engineered outer vocal fold replacement is derived both from initially embedded adipose-derived stromal cells and infiltrating native cells. Our results suggest this tissue-engineering approach can provide a well-integrated tissue graft with prolonged cell activity for repair of severe vocal fold scars.

Dynamics of phonatory posturing at phonation onset.

INTRODUCTION: In speech and singing, the intrinsic laryngeal muscles set the prephonatory posture prior to the onset of phonation. The timing and shape of the prephonatory glottal posture can directly affect the resulting phonation type. We investigated the dynamics of human laryngeal phonatory posturing. METHODS: Onset of vocal fold adduction to phonation was observed in 27 normal subjects using high-speed video recording. Subjects were asked to utter a variety of phonation types (modal, breathy, pressed, /i/ following sniff). Digital videokymography with concurrent acoustic signal was analyzed to assess the timing of the following: onset of adduction to final phonatory posture (FPT), phonation onset time (POT), and phonatory posture time (PPT). Final phonatory posture time was determined as the moment at which the laryngeal configuration used in phonation was first achieved. RESULTS: Thirty-three audiovisual recordings met inclusion criteria. Average FPT, PPT, and POT were as follows: 303, 106, and 409 ms for modal; 430, 104, and 534 ms for breathy; 483, 213, and 696 ms for pressed; and 278, 98, and 376 ms for sniff-/i/. The following posturing features were observed: 1) pressed phonation: increased speed of closure just prior to final posture, complete glottal closure, and increased supraglottic hyperactivity; and 2) breathy phonation: decreased speed of closure prior to final posture, increased posterior glottal gap, and increased midmembranous gap. CONCLUSIONS: Phonation onset latency was shortest for modal and longest for pressed voice. These findings are likely explained by glottal resistance and subglottal pressure requirements. LEVEL OF EVIDENCE: NA. Laryngoscope, 126:1837-1843, 2016.

Tissue-Engineered Vocal Fold Mucosa Implantation in Rabbits.

OBJECTIVE: To assess phonatory function and wound healing of a tissue-engineered vocal fold mucosa (TE-VFM) in rabbits. An "artificial" vocal fold would be valuable for reconstructing refractory scars and resection defects, particularly one that uses readily available autologous cells and scaffold. This work implants a candidate TE-VFM after resecting native epithelium and lamina propria in rabbits. STUDY DESIGN: Prospective animal study. SETTING: Research laboratory. SUBJECTS AND METHODS: Rabbit adipose-derived stem cells were isolated and cultured in three-dimensional fibrin scaffolds to form TE-VFM. Eight rabbits underwent laryngofissure, unilateral European Laryngologic Society type 2 cordectomy, and immediate reconstruction with TE-VFM. After 4 weeks, larynges were excised, phonated, and examined by histology. RESULTS: Uniform TE-VFM implants were created, with rabbit mesenchymal cells populated throughout fibrin hydrogels. Rabbits recovered uneventfully after implantation. Phonation was achieved in all, with mucosal waves evident at the implant site. Histology after 4 weeks showed resorbed fibrin matrix, continuous epithelium, and mildly increased collagen relative to contralateral unoperated vocal folds. Elastic fiber appearance was highly variable. Inflammatory cell infiltrate was limited to animals receiving sex-mismatched implants. CONCLUSION: TE-VFMs were successfully implanted into 8 rabbits, with minor evidence of scar formation and immune reaction. Vibration was preserved 4 weeks after resecting and reconstructing the complete vocal fold cover layer. Further studies will investigate the mechanism and durability of improvement. TE-VFM with autologous cells is a promising new approach for vocal fold reconstruction.

Photodocumentation of the development of type I posterior glottic stenosis after intubation injury.

Bilateral vocal fold immobility may result from bilateral recurrent laryngeal nerve paralysis or physiologic insults to the airway such as glottic scars. The progression of mucosal injury to granulation tissue, and then posterior glottis stenosis, is an accepted theory but has not been photodocumented. This paper presents serial images from common postintubation injury to less common posterior glottic stenosis with interarytenoid synechia.

Laryngomalacia presenting as recurrent croup in an infant.

Laryngomalacia is a common disease of infancy which can present with atypical symptoms and at an atypical age, causing the diagnosis to often be overlooked. We report a case of a male patient who was diagnosed with laryngomalacia at the age of three months. The patient's inspiratory stridor resolved within a year, but he went on to develop atypical croup. The patient was later diagnosed with severe laryngomalacia which complicated his "croup-like" symptoms. He subsequently underwent supraglottoplasty with complete resolution of symptoms.

Lentiviral transduction of face and limb flaps: implications for immunomodulation of vascularized composite allografts.

BACKGROUND: Ex vivo introduction of an immunomodulatory transgene into a face or hand allograft may improve the risk-to-benefit ratio of vascularized composite allografts. Abrogation of the immunogenicity of the skin component of a face or hand allograft may decrease alloreactivity and permit the induction of immunologic tolerance. Proof-of-principle demonstrations of transduction of composite tissue have been established using adenoviral vectors, producing transient gene expression. The authors hypothesized that transduction, integration, and long-term expression of transgenes in a vascularized composite allograft could be achieved using lentiviral vectors. METHODS: Ex vivo transduction of heterogeneous primary rat cell lines representative of a composite tissue flap's cellular architecture was performed using a luc-enhanced green fluorescent protein (eGFP) human immunodeficiency virus-1-based lentiviral vector. Ex vivo injections of rat superficial inferior epigastric artery flaps with the viral vector were performed intraarterially, intramuscularly, and intradermally. RESULTS: Quantifiable reporter expression by flow cytometry (fluorescence-activated cell sorting) analysis and in vitro bioluminescence was observed. The luc-eGFP vector exhibited broad tropism and allowed transgene expression in relevant cell lines and throughout the flaps. Ex vivo intradermal transfection resulted in genomic integration and long-term constitutive gene expression (>150 days). Similarly, efficient intradermal transfection of face and hand flaps in a rat model corroborated this approach. Ex vivo intravascular perfusion of the vector proved inferior to intradermal injection. CONCLUSIONS: Intradermal delivery of the transgenes proved superior to intravascular perfusion. Optimization of this gene-delivery approach may allow long-term, constitutive expression of immunomodulatory proteins in face and hand allografts. Future goals include replacement of the luciferase and eGFP reporter genes with key immunomodulatory proteins.

Negative feedback in noncanonical NF-kappaB signaling modulates NIK stability through IKKalpha-mediated phosphorylation.

Canonical and noncanonical nuclear factor kappaB (NF-kappaB) signaling are the two basic pathways responsible for the release of NF-kappaB dimers from their inhibitors. Enhanced NF-kappaB signaling leads to inflammatory and proliferative diseases; thus, inhibitory pathways that limit its activity are critical. Whereas multiple negative feedback mechanisms control canonical NF-kappaB signaling, none has been identified for the noncanonical pathway. Here, we describe a mechanism of negative feedback control of noncanonical NF-kappaB signaling that attenuated the stabilization of NF-kappaB-inducing kinase (NIK), the central regulatory kinase of the noncanonical pathway, induced by B cell-activating factor receptor (BAFF-R) and lymphotoxin beta receptor (LTbetaR). Inhibitor of kappaB (IkappaB) kinase alpha (IKKalpha) was previously thought to lie downstream of NIK in the noncanonical NF-kappaB pathway; we showed that phosphorylation of NIK by IKKalpha destabilized NIK. In the absence of IKKalpha-mediated negative feedback, the abundance of NIK increased after receptor ligation. A form of NIK with mutations in the IKKalpha-targeted serine residues was more stable than wild-type NIK and resulted in increased noncanonical NF-kappaB signaling. Thus, in addition to the regulation of the basal abundance of NIK in unstimulated cells by a complex containing tumor necrosis factor receptor-associated factor (TRAF) and cellular inhibitor of apoptosis (cIAP) proteins, IKKalpha-dependent destabilization of NIK prevents the uncontrolled activity of the noncanonical NF-kappaB pathway after receptor ligation.

Regulation of antiviral responses by a direct and specific interaction between TRAF3 and Cardif.

Upon recognition of viral infection, RIG-I and Helicard recruit a newly identified adapter termed Cardif, which induces type I interferon (IFN)-mediated antiviral responses through an unknown mechanism. Here, we demonstrate that TRAF3, like Cardif, is required for type I interferon production in response to intracellular double-stranded RNA. Cardif-mediated IFNalpha induction occurs through a direct interaction between the TRAF domain of TRAF3 and a TRAF-interaction motif (TIM) within Cardif. Interestingly, while the entire N-terminus of TRAF3 was functionally interchangeable with that of TRAF5, the TRAF domain of TRAF3 was not. Our data suggest that this distinction is due to an inability of the TRAF domain of TRAF5 to bind the TIM of Cardif. Finally, we show that preventing association of TRAF3 with this TIM by mutating two critical amino acids in the TRAF domain also abolishes TRAF3-dependent IFN production following viral infection. Thus, our findings suggest that the direct and specific interaction between the TRAF domain of TRAF3 and the TIM of Cardif is required for optimal Cardif-mediated antiviral responses.