Nanoparticle Concentration in Surgical Plume During Tonsillectomy: A Comparison of Four Techniques

OBJECTIVE

Surgical plume has known potential occupational health hazards. This study compares nanoparticle concentrations in surgical plumes generated between different pediatric tonsillectomy surgical techniques and assesses the efficacy of mitigation measures.

METHODS

This is a cross-sectional study performed at a tertiary care academic center. Extracapsular or intracapsular tonsillectomy was performed in 60 patients using four techniques and in 10 additional patients using mitigation measures. Two nanoparticle counters were used to measure particulate concentrations: CPC™ and DiSCmini™. Tonsillectomy techniques included: (1) microdebrider (MD), (2) Bovie with manual suctioning by an assistant (B), (3) Bovie with built-in smoke evacuation system (BS), and (4) Coblator™ (CB). An additional Yankauer suction was used in the mitigation groups (BSY) and (CBY). Comparative analysis was performed using one-way ANOVA on ranks and pairwise comparisons between the groups.

RESULTS

The mean concentrations (particles/cm3) and coefficient of variants for the DiSCmini particulate counter were MD: 5140 (1.6), B: 30700 (1.5), BS: 25001 (0.8), CB: 54814 (1.7), CBY: 2395 (1.3) and BSY: 11552 (1.0). Mean concentrations for the CPC particulate counter were MD: 1223 (1.4), B: 3405 (0.7), BS: 5002 (0.9), CB: 13273 (1.0), CBY: 1048 (1.2) and BSY: 3046 (0.6). The lowest mean concentrations were noted in cases using MD and the highest in cases using CB. However, after mitigation, CBY had the lowest overall levels.

CONCLUSION

Tonsillectomy technique does impact the levels of nanoparticles emitted within the surgical plume, which may present an occupational hazard for operating room personnel.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:2444-2448, 2024.

Modulated Fibrosis and Mechanosensing of Fibroblasts by SB525334 in Pediatric Subglottic Stenosis

OBJECTIVE

Subglottic stenosis (SGS) may result from prolonged intubation where fibrotic scar tissue narrows the airway. The scar forms by differentiated myofibroblasts secreting excessive extracellular matrix (ECM). TGF-β1 is widely accepted as a regulator of fibrosis; however, it is unclear how biomechanical pathways co-regulate fibrosis. Therefore, we phenotyped fibroblasts from pediatric patients with SGS to explore how key signaling pathways, TGF-β and Hippo, impact scarring and assess the impact of inhibiting these pathways with potential therapeutic small molecules SB525334 and DRD1 agonist dihydrexidine hydrochloride (DHX).

METHODS

Laryngeal fibroblasts isolated from subglottic as well as distal control biopsies of patients with evolving and maturing subglottic stenosis were assessed by α-smooth muscle actin immunostaining and gene expression for α-SMA, FN, HGF, and CTGF markers. TGF-β and Hippo signaling pathways were modulated during TGF-β1-induced fibrosis using the inhibitor SB525334 or DHX and analyzed by RT-qPCR for differential gene expression and atomic force microscopy for ECM stiffness.

RESULTS

SGS fibroblasts exhibited higher α-SMA staining and greater inflammatory cytokine and fibrotic marker expression upon TGF-β1 stimulation (p < 0.05). SB525334 restored levels to baseline by reducing SMAD2/3 nuclear translocation (p < 0.0001) and pro-fibrotic gene expression (p < 0.05). ECM stiffness of stenotic fibroblasts was greater than healthy fibroblasts and was restored to baseline by Hippo pathway modulation using SB525334 and DHX (p < 0.01).

CONCLUSION

We demonstrate that distinct fibroblast phenotypes from diseased and healthy regions of pediatric SGS patients respond differently to TGF-β1 stimulation, and SB525334 has the superior potential for subglottic stenosis treatment by simultaneously modulating TGF-β and Hippo signaling pathways.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:287-296, 2024.

Anatomic Considerations of esophageal button battery ingestion for outcomes and imaging

INTRODUCTION

Button batteries (BB) are a source of significant morbidity and mortality in young children. Little data is available regarding associations between esophageal impaction location and outcomes or need for surveillance imaging.

METHODS

All patients treated at a single institution following BB ingestion between 2018 and 2022 were included for retrospective chart review.

RESULTS

Twenty patients were treated at our institution BBs were located, or most significant damage observed, in the cervical esophagus (n = 10, 50 %), followed by thoracic esophagus (n = 6, 30 %), and abdominal esophagus (n = 4, 20 %). Patients with cervical esophageal impaction were younger (482 [370-866] days), than those with thoracic (1395 [871-2369] days) or abdominal esophageal impaction (2021.5 [1230.5-3419.5] days) (p = 0.003). Zargar Mucosal Injury Grade was significantly more severe in patients with cervical button battery impaction; 8/10 (80 %) had a ≥Grade IIIB injury, compared to 2/6 (33.3 %) thoracic impactions and 0/4 (0 %) abdominal impactions (p = 0.002). All patients who developed persistent esophageal stenosis (n = 6) had cervical battery impactions (6, 60 %, p = 0.015). Both TEFs (2/2) had anterior facing anode, while both (2/2) esophageal perforations had posterior. Only 1/20 (5 %) patients, and 1/7 (14.3 %) with serious complications, had a serious complication detected on routine, rather than clinically indicated follow-up surveillance.

CONCLUSIONS

In our population, cervical BB impaction occurred more frequently in younger children, was associated with more severe mucosal injury, and had higher risk of stenosis. Nearly all complications were detected on clinically indicated rather than postoperative surveillance imaging.

Association of Diet Patterns and Post-Operative Tympanostomy Tube Otorrhea: A Pilot Study

OBJECTIVE

The objective of this study was to explore diet patterns in children with tympanostomy tube placement (TTP) complicated by postoperative tympanostomy tube otorrhea.

STUDY DESIGN

Cross-sectional survey and retrospective cohort study.

METHODS

Caregivers of children (0-12 years old), at a tertiary-care pediatric hospital who underwent TTP within 6 months to 2 years prior to enrollment were included. Children with a history of Down syndrome, cleft palate, craniofacial syndromes, known immunodeficiency, or a non-English-speaking family were excluded. Our primary outcome variable was the number of otorrhea episodes. The primary predictor was diet patterns, particularly dessert intake, which was captured through a short food questionnaire.

RESULTS

A total of 286 participants were included in this study. The median age was 1.8 years (IQR, 1.3, 2.9). A total of 174 (61%) participants reported at least one episode of otorrhea. Children who consumed dessert at least two times per week had a higher risk of otorrhea compared to children who consumed one time per week or less (odds ratio [OR], 3.22, 95% Confidence Interval [CI]: 1.69, 6.12). The odds ratio increase continued when considering more stringent criteria for otorrhea (multiple episodes or one episode occurring 4 weeks after surgery), with a 2.33 (95% CI: 1.24, 4.39) higher odds of otorrhea in children with dessert intake at least 2 times per week.

CONCLUSIONS

Our pilot data suggest that episodes of otorrhea among children with TTP were associated with more frequent dessert intake. Future studies using prospectively administered diet questionnaires are necessary to confirm these findings.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:3575-3581, 2023.

Tracheostomy in the extremely premature neonate - Long term outcomes in a multi-institutional study

OBJECTIVES

To describe the long-term outcomes related to breathing, feeding, and neurocognitive development in extremely premature infants requiring tracheostomy.

STUDY DESIGN

Pooled cross-sectional survey.

SETTING

Multi-institutional academic children's hospitals.

METHODS

Extremely premature infants who underwent tracheostomy between January 1, 2012, and December 31, 2019, at four academic hospitals were identified from an existing database. Information was gathered from responses to a questionnaire by caregivers regarding airway status, feeding, and neurodevelopment 2-9 years after tracheostomy.

RESULTS

Data was available for 89/91 children (96.8%). The mean gestational age was 25.5 weeks (95% CI 25.2-25.7) and mean birth weight was 0.71 kg (95% CI 0.67-0.75). Mean post gestational age at tracheostomy was 22.8 weeks (95% CI 19.0-26.6). At time of the survey, 18 (20.2%) were deceased. 29 (40.8%) maintained a tracheostomy, 18 (25.4%) were on ventilatory support, and 5 (7%) required 24-h supplemental oxygen. Forty-six (64.8%) maintained a gastrostomy tube, 25 (35.2%) had oral dysphagia, and 24 (33.8%) required a modified diet. 51 (71.8%) had developmental delay, 45 (63.4%) were enrolled in school of whom 33 (73.3%) required special education services.

CONCLUSIONS

Tracheostomy in extremely premature neonates is associated with long term morbidity in the pulmonary, feeding, and neurocognitive domains. At time of the survey, about half are decannulated, with a majority weaned off ventilatory support indicating improvement in lung function with age. Feeding dysfunction is persistent, and a significant number will have some degree of neurocognitive dysfunction at school age. This information may help caregivers regarding expectations and plans for resource management.

Neuroinflammation, its Role in Alzheimer's Disease and Therapeutic Strategie

Neuroinflammation precedes the clinical onset of various neurodegenerative diseases, including Alzheimer's disease (AD), by years or frequently even decades (1-3). In terms of the underlying physiology, there is a great need for understanding and controlling interactions between the central nervous system (CNS) and the immune system in an attempt to develop approaches to prevent or delay the disease's progression. Nerve cells have limited motion capability, whereas immune cells can migrate freely via circulation. This difference raises a variety of questions in the context of senile plaque formation and phagocytosis. Broad-scale unbiased genomic studies bring several genetic variants such as sialic acid binding Ig-like lectin 3 (CD33), triggering receptor expressed on myeloid cells 2 (TREM2) or complement receptor type 1 (CR1) into the focus of researchers' attention as potential risk factors for neuroinflammation. In addition, advanced proteomic analyses have been revealing links between these genetic contributors and complex, malfunctioning signaling pathways (including the upregulation of factors like tumor necrosis factor TNF-α, tumor growth factor TGF-β and interleukin IL-1α) that promote proinflammatory mechanisms via intracellular signaling and trafficking, synaptic function, and cell metabolism/ proliferation. In AD, the brain's microglia and astrocytes, which are normally responsible for maintaining the homeostasis of synaptic transmission and its remodeling by pruning, are the initiators of neuroinflammation and toxic tau and amyloid-β (Aβ) accumulation. Thus, they drive the CNS into a state of sustained or even self-accelerated deterioration. Here we aim to review the cell types and mediators involved in neuroinflammation and AD, the symptom manifestation in clinical settings, and potential candidates for improving diagnosis and treatment.

Expert Consensus Statement: Pediatric Drug-Induced Sleep Endoscopy

OBJECTIVE

To develop an expert consensus statement on pediatric drug-induced sleep endoscopy (DISE) that clarifies controversies and offers opportunities for quality improvement. Pediatric DISE was defined as flexible endoscopy to examine the upper airway of a child with obstructive sleep apnea who is sedated and asleep.

METHODS

Development group members with expertise in pediatric DISE followed established guidelines for developing consensus statements. A search strategist systematically reviewed the literature, and the best available evidence was used to compose consensus statements regarding DISE in children 0 to 18 years old. Topics with significant practice variation and those that would improve the quality of patient care were prioritized.

RESULTS

The development group identified 59 candidate consensus statements, based on 50 initial proposed topics, that focused on addressing the following high-yield topics: (1) indications and utility, (2) protocol, (3) optimal sedation, (4) grading and interpretation, (5) complications and safety, and (6) outcomes for DISE-directed surgery. After 2 iterations of the Delphi survey and removal of duplicative statements, 26 statements met the criteria for consensus; 11 statements were designated as no consensus. Several areas, such as the role of DISE at the time of adenotonsillectomy, were identified as needing further research.

CONCLUSION

Expert consensus was achieved for 26 statements pertaining to indications, protocol, and outcomes for pediatric DISE. Clinicians can use these statements to improve quality of care, inform policy and protocols, and identify areas of uncertainty. Future research, ideally randomized controlled trials, is warranted to address additional controversies related to pediatric DISE.

Timing the First Pediatric Tracheostomy Tube Change: A Randomized Controlled Trial

OBJECTIVE

The first pediatric tracheostomy tube change often occurs within 7 days after placement; however, the optimal timing is not known. The primary objective was to determine the rate of adverse events of an early tube change. Secondary objectives compared rates of significant peristomal wounds, sedation requirements, and expedited intensive care discharges.

STUDY DESIGN

Prospective randomized controlled trial.

SETTING

Tertiary children's hospital between October 2018 and April 2020.

METHODS

A randomized controlled trial enrolled children under 24 months to early (day 4) or late (day 7) first tracheostomy tube changes.

RESULTS

Sixteen children were enrolled with 10 randomized to an early change. Median age was 5.9 months (interquartile range, 5.4-8.3), and 86.7% required tracheostomy for respiratory failure. All tracheostomy tube changes were performed without adverse events. There were no accidental decannulations. Significant wounds developed in 10% of children with early tracheostomy tube changes and 83.3% of children with late tracheostomy tube changes (odds ratio [OR], 45.0; 95% CI, 2.3-885.6; P = .01). This significant reduction in wound complications justified concluding trial enrollment. Hours of dexmedetomidine sedation (P = .11) and boluses of midazolam during the first 7 days (P = .08) were no different between groups. After the first change, 90% of the early group were discharged from intensive care within 5 weeks compared to 33.3% of patients in the late group (OR, 18.0; 95% CI, 1.2-260.9; P = .03).

CONCLUSION

The first tracheostomy tube change in children can occur without adverse events on day 4, resulting in fewer significant peristomal wounds and earlier intensive care discharge.

Algorithm-Based Pediatric Otolaryngology Management During the COVID-19 Global Pandemic: A Children’s Hospital of Philadelphia Clinical Consensus

Objective

The coronavirus disease 2019 (COVID-19) pandemic requires clinicians to explore alternatives to routine patient management. Otolaryngologists caring for children commonly depend on physical examination, laboratory data, and ambulatory surgical procedures. Limiting patient care, mindful allocation of resources, and concern for safety have challenged all aspects of our health care system. This evidence-based clinical consensus is designed to guide practitioners of pediatric otolaryngology for common scenarios during this time.

Data Sources

Peer-reviewed literature, published reports, institutional guidelines, and expert consensus.

Review Methods

A clinical consensus on 6 common scenarios in pediatric otolaryngology developed with evidence-based strategies.

Conclusions

Providers should suspend all in-person nonessential office visits and elective surgical procedures. An emphasis on medical management and caregiver education will provide reasonable approaches to many of the common outpatient concerns. Surgery for chronic otitis media, obstructive sleep apnea, and acute rhinosinusitis should occur only in response to severe complications or failure of medical regimens. The approach to the pediatric neck mass focuses on timely management for oncologic etiologies and cautious surgical intervention for abscess drainage or tissue sampling. Finally, epistaxis and otorrhea must be triaged and addressed without the usual ambulatory procedures.

Implications for Practice

Adaptation of practice patterns during this unprecedented moment for our health care system requires thoughtful planning. The strategies described allow for safe handling of common pediatric otolaryngology diagnoses. Ultimately, otolaryngologists must be stewards of our global health community while advocating for the care of individual pediatric patients.

Management and Outcomes of Button Batteries in the Aerodigestive Tract: A Multi-institutional Study

OBJECTIVES/HYPOTHESIS

To describe the clinical presentation, management, and complications associated with button battery impaction in the aerodigestive tract in children.

STUDY DESIGN

Retrospective case series.

METHODS

This multi-institutional study, endorsed by the American Society of Pediatric Otolaryngology research consortium, is a retrospective medical record review, including all children at five tertiary-care institutions presenting with button batteries impacted in the aerodigestive tract between January 2002 and December 2014. Battery type/size, duration and location of impaction, presenting symptoms, treatment, complications, and outcomes were examined.

RESULTS

Eighty-one patients were included (64.2% male), with ingestion witnessed in 20 (24.7%). Median age at presentation was 3 years (range, 1 week-14 years). Median time from diagnosis to removal was 2.5 hours (range, 0.4-72 hours). Locations included the esophagus (n = 48), hypopharynx (n = 1), stomach (n = 6), nasal cavity (n = 22), and ear canal (n = 4). Most common symptoms for esophageal/hypopharyngeal impactions included dysphagia (26.5%), nausea/vomiting (26.5%), drooling (24.5%), cough (18.4%), and fever (18.4%). Most common symptoms for nasal impactions included epistaxis (54.6%), rhinorrhea (40.9%), nasal pain (27.3%), and fever (22.7%). Almost all esophageal impactions were from 3-V (89.5%), 20-mm (81.8%) lithium batteries. Severe esophageal complications included stricture (28.6%), perforation (24.5%), tracheoesophageal fistula formation (8.2%), pneumothorax (4.1%), and bilateral true vocal fold paresis (4.1%). Nasal complications included necrosis (59.1%), septal perforation (27.3%), and saddle nose deformity (4.5%). Duration of impaction correlated with an increased likelihood of persistent symptoms only for nasal batteries (P = .049).

CONCLUSIONS

Button batteries in the upper pediatric aerodigestive tract or ear canal should be considered a surgical emergency, requiring urgent removal and careful vigilance for complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E298-E306, 2021.

Clinical Practice Guideline: Tonsillectomy in Children (Update)

OBJECTIVE

This update of a 2011 guideline developed by the American Academy of Otolaryngology-Head and Neck Surgery Foundation provides evidence-based recommendations on the pre-, intra-, and postoperative care and management of children 1 to 18 years of age under consideration for tonsillectomy. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil, including its capsule, by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Tonsillectomy is one of the most common surgical procedures in the United States, with 289,000 ambulatory procedures performed annually in children <15 years of age based on the most recent published data. This guideline is intended for all clinicians in any setting who interact with children who may be candidates for tonsillectomy.

PURPOSE

The purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing children under consideration for tonsillectomy and to create explicit and actionable recommendations to implement these opportunities in clinical practice. Specifically, the goals are to educate clinicians, patients, and/or caregivers regarding the indications for tonsillectomy and the natural history of recurrent throat infections. Additional goals include the following: optimizing the perioperative management of children undergoing tonsillectomy, emphasizing the need for evaluation and intervention in special populations, improving the counseling and education of families who are considering tonsillectomy for their children, highlighting the management options for patients with modifying factors, and reducing inappropriate or unnecessary variations in care. Children aged 1 to 18 years under consideration for tonsillectomy are the target patient for the guideline. For this guideline update, the American Academy of Otolaryngology-Head and Neck Surgery Foundation selected a panel representing the fields of nursing, anesthesiology, consumers, family medicine, infectious disease, otolaryngology-head and neck surgery, pediatrics, and sleep medicine.

KEY ACTION STATEMENTS

The guideline update group made strong recommendations for the following key action statements (KASs): (1) Clinicians should recommend watchful waiting for recurrent throat infection if there have been <7 episodes in the past year, <5 episodes per year in the past 2 years, or <3 episodes per year in the past 3 years. (2) Clinicians should administer a single intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. (3) Clinicians should recommend ibuprofen, acetaminophen, or both for pain control after tonsillectomy. The guideline update group made recommendations for the following KASs: (1) Clinicians should assess the child with recurrent throat infection who does not meet criteria in KAS 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergies/intolerance, PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis), or history of >1 peritonsillar abscess. (2) Clinicians should ask caregivers of children with obstructive sleep-disordered breathing and tonsillar hypertrophy about comorbid conditions that may improve after tonsillectomy, including growth retardation, poor school performance, enuresis, asthma, and behavioral problems. (3) Before performing tonsillectomy, the clinician should refer children with obstructive sleep-disordered breathing for polysomnography if they are <2 years of age or if they exhibit any of the following: obesity, Down syndrome, craniofacial abnormalities, neuromuscular disorders, sickle cell disease, or mucopolysaccharidoses. (4) The clinician should advocate for polysomnography prior to tonsillectomy for obstructive sleep-disordered breathing in children without any of the comorbidities listed in KAS 5 for whom the need for tonsillectomy is uncertain or when there is discordance between the physical examination and the reported severity of oSDB. (5) Clinicians should recommend tonsillectomy for children with obstructive sleep apnea documented by overnight polysomnography. (6) Clinicians should counsel patients and caregivers and explain that obstructive sleep-disordered breathing may persist or recur after tonsillectomy and may require further management. (7) The clinician should counsel patients and caregivers regarding the importance of managing posttonsillectomy pain as part of the perioperative education process and should reinforce this counseling at the time of surgery with reminders about the need to anticipate, reassess, and adequately treat pain after surgery. (8) Clinicians should arrange for overnight, inpatient monitoring of children after tonsillectomy if they are <3 years old or have severe obstructive sleep apnea (apnea-hypopnea index ≥10 obstructive events/hour, oxygen saturation nadir <80%, or both). (9) Clinicians should follow up with patients and/or caregivers after tonsillectomy and document in the medical record the presence or absence of bleeding within 24 hours of surgery (primary bleeding) and bleeding occurring later than 24 hours after surgery (secondary bleeding). (10) Clinicians should determine their rate of primary and secondary posttonsillectomy bleeding at least annually. The guideline update group made a strong recommendation against 2 actions: (1) Clinicians should not administer or prescribe perioperative antibiotics to children undergoing tonsillectomy. (2) Clinicians must not administer or prescribe codeine, or any medication containing codeine, after tonsillectomy in children younger than 12 years. The policy level for the recommendation about documenting recurrent throat infection was an option: (1) Clinicians may recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year, at least 5 episodes per year for 2 years, or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and ≥1 of the following: temperature >38.3°C (101°F), cervical adenopathy, tonsillar exudate, or positive test for group A beta-hemolytic streptococcus.

DIFFERENCES FROM PRIOR GUIDELINE

(1) Incorporating new evidence profiles to include the role of patient preferences, confidence in the evidence, differences of opinion, quality improvement opportunities, and any exclusion to which the action statement does not apply. (2) There were 1 new clinical practice guideline, 26 new systematic reviews, and 13 new randomized controlled trials included in the current guideline update. (3) Inclusion of 2 consumer advocates on the guideline update group. (4) Changes to 5 KASs from the original guideline: KAS 1 (Watchful waiting for recurrent throat infection), KAS 3 (Tonsillectomy for recurrent infection with modifying factors), KAS 4 (Tonsillectomy for obstructive sleep-disordered breathing), KAS 9 (Perioperative pain counseling), and KAS 10 (Perioperative antibiotics). (5) Seven new KASs: KAS 5 (Indications for polysomnography), KAS 6 (Additional recommendations for polysomnography), KAS 7 (Tonsillectomy for obstructive sleep apnea), KAS 12 (Inpatient monitoring for children after tonsillectomy), KAS 13 (Postoperative ibuprofen and acetaminophen), KAS 14 (Postoperative codeine), and KAS 15a (Outcome assessment for bleeding). (6) Addition of an algorithm outlining KASs. (7) Enhanced emphasis on patient and/or caregiver education and shared decision making.

Clinical Practice Guideline: Tonsillectomy in Children (Update)-Executive Summary

OBJECTIVE

This update of a 2011 guideline developed by the American Academy of Otolaryngology-Head and Neck Surgery Foundation provides evidence-based recommendations on the pre-, intra-, and postoperative care and management of children 1 to 18 years of age under consideration for tonsillectomy. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil, including its capsule, by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Tonsillectomy is one of the most common surgical procedures in the United States, with 289,000 ambulatory procedures performed annually in children <15 years of age, based on the most recent published data. This guideline is intended for all clinicians in any setting who interact with children who may be candidates for tonsillectomy.

PURPOSE

The purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing children under consideration for tonsillectomy and to create explicit and actionable recommendations to implement these opportunities in clinical practice. Specifically, the goals are to educate clinicians, patients, and/or caregivers regarding the indications for tonsillectomy and the natural history of recurrent throat infections. Additional goals include the following: optimizing the perioperative management of children undergoing tonsillectomy, emphasizing the need for evaluation and intervention in special populations, improving the counseling and education of families who are considering tonsillectomy for their children, highlighting the management options for patients with modifying factors, and reducing inappropriate or unnecessary variations in care. Children aged 1 to 18 years under consideration for tonsillectomy are the target patient for the guideline. For this guideline update, the American Academy of Otolaryngology-Head and Neck Surgery Foundation selected a panel representing the fields of nursing, anesthesiology, consumers, family medicine, infectious disease, otolaryngology-head and neck surgery, pediatrics, and sleep medicine.

KEY ACTION STATEMENTS

The guideline update group made strong recommendations for the following key action statements (KASs): (1) Clinicians should recommend watchful waiting for recurrent throat infection if there have been <7 episodes in the past year, <5 episodes per year in the past 2 years, or <3 episodes per year in the past 3 years. (2) Clinicians should administer a single intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. (3) Clinicians should recommend ibuprofen, acetaminophen, or both for pain control after tonsillectomy. The guideline update group made recommendations for the following KASs: (1) Clinicians should assess the child with recurrent throat infection who does not meet criteria in KAS 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergies/intolerance, PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis), or history of >1 peritonsillar abscess. (2) Clinicians should ask caregivers of children with obstructive sleep-disordered breathing and tonsillar hypertrophy about comorbid conditions that may improve after tonsillectomy, including growth retardation, poor school performance, enuresis, asthma, and behavioral problems. (3) Before performing tonsillectomy, the clinician should refer children with obstructive sleep-disordered breathing for polysomnography if they are <2 years of age or if they exhibit any of the following: obesity, Down syndrome, craniofacial abnormalities, neuromuscular disorders, sickle cell disease, or mucopolysaccharidoses. (4) The clinician should advocate for polysomnography prior to tonsillectomy for obstructive sleep-disordered breathing in children without any of the comorbidities listed in KAS 5 for whom the need for tonsillectomy is uncertain or when there is discordance between the physical examination and the reported severity of obstructive sleep-disordered breathing. (5) Clinicians should recommend tonsillectomy for children with obstructive sleep apnea documented by overnight polysomnography. (6) Clinicians should counsel patients and caregivers and explain that obstructive sleep-disordered breathing may persist or recur after tonsillectomy and may require further management. (7) The clinician should counsel patients and caregivers regarding the importance of managing posttonsillectomy pain as part of the perioperative education process and should reinforce this counseling at the time of surgery with reminders about the need to anticipate, reassess, and adequately treat pain after surgery. (8) Clinicians should arrange for overnight, inpatient monitoring of children after tonsillectomy if they are <3 years old or have severe obstructive sleep apnea (apnea-hypopnea index ≥10 obstructive events/hour, oxygen saturation nadir <80%, or both). (9) Clinicians should follow up with patients and/or caregivers after tonsillectomy and document in the medical record the presence or absence of bleeding within 24 hours of surgery (primary bleeding) and bleeding occurring later than 24 hours after surgery (secondary bleeding). (10) Clinicians should determine their rate of primary and secondary posttonsillectomy bleeding at least annually. The guideline update group made a strong recommendation against 2 actions: (1) Clinicians should not administer or prescribe perioperative antibiotics to children undergoing tonsillectomy. (2) Clinicians must not administer or prescribe codeine, or any medication containing codeine, after tonsillectomy in children younger than 12 years. The policy level for the recommendation about documenting recurrent throat infection was an option: (1) Clinicians may recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year, at least 5 episodes per year for 2 years, or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and ≥1 of the following: temperature >38.3°C (101°F), cervical adenopathy, tonsillar exudate, or positive test for group A beta-hemolytic streptococcus.

DIFFERENCES FROM PRIOR GUIDELINE

Incorporating new evidence profiles to include the role of patient preferences, confidence in the evidence, differences of opinion, quality improvement opportunities, and any exclusion to which the action statement does not apply. There were 1 new clinical practice guideline, 26 new systematic reviews, and 13 new randomized controlled trials included in the current guideline update. Inclusion of 2 consumer advocates on the guideline update group. Changes to 5 KASs from the original guideline: KAS 1 (Watchful waiting for recurrent throat infection), KAS 3 (Tonsillectomy for recurrent infection with modifying factors), KAS 4 (Tonsillectomy for obstructive sleep-disordered breathing), KAS 9 (Perioperative pain counseling), and KAS 10 (Perioperative antibiotics). Seven new KASs: KAS 5 (Indications for polysomnography), KAS 6 (Additional recommendations for polysomnography), KAS 7 (Tonsillectomy for obstructive sleep apnea), KAS 12 (Inpatient monitoring for children after tonsillectomy), KAS 13 (Postoperative ibuprofen and acetaminophen), KAS 14 (Postoperative codeine), and KAS 15a (Outcome assessment for bleeding). Addition of an algorithm outlining KASs. Enhanced emphasis on patient and/or caregiver education and shared decision making.

Plain Language Summary for Patients: Tonsillectomy in Children

This plain language summary for patients serves as an overview explaining tonsillectomy in children and to help patients, caregivers, and clinicians in their discussions about the reasons that a tonsillectomy may be needed, management options, and care related to the procedure. This summary applies to patients ages 1 through 18 years and is based on the 2019 "Clinical Practice Guideline: Tonsillectomy in Children (Update)." This evidence-based guideline mainly addresses the need for tonsillectomy based on breathing problems that take place during sleep and repeated sore throats or "tonsillitis." The guideline was developed to identify quality improvement opportunities in managing children under consideration for tonsillectomy and to create clear recommendations for clinicians to use in medical practice.

Association Between Ibuprofen Use and Severity of Surgically Managed Posttonsillectomy Hemorrhage

Importance

Ibuprofen used in postoperative management of pain after tonsillectomy has not been shown to increase the overall risk for posttonsillectomy hemorrhage (PTH). The severity of bleeding is difficult to quantify but may be a more important outcome to measure.

Objective

To evaluate the association between ibuprofen use and severity of PTH using transfusion events as a marker of severity.

Design, Setting, and Participants

This retrospective cohort study identified 8868 patients who underwent tonsillectomy from January 20, 2011, through June 30, 2014, at the tertiary academic Children's Hospital of Philadelphia. Of these patients, 6710 met the inclusion criteria. Data were collected using electronic database acquisition and query.

Main Outcomes and Measures

Multivariate analysis was performed to identify independent prognostic factors for PTH and receipt of transfusion.

Results

Of the 6710 patients who met criteria for analysis (3454 male [51.5%] and 3256 female [48.5%]; median age, 5.4 years [interquartile range, 3.7-8.2 years]), 222 (3.3%) presented with PTH that required surgical control (sPTH). A total of 15 of the 8868 patients required transfusion for an overall risk for transfusion after tonsillectomy of 0.2%. Fifteen of 222 patients undergoing sPTH (6.8%) received transfusions. No significant independent increased risk for sPTH was associated with use of ibuprofen (adjusted odds ratio [OR], 0.90; 95% CI, 0.68-1.19). A significant independent association was found in the risk for sPTH in patients 12 years or older (adjusted OR, 2.74; 95% CI, 1.99-3.76) and in patients with a history of recurrent tonsillitis (adjusted OR, 1.52; 95% CI, 1.12-2.06). When using transfusion rates as a surrogate for severity of sPTH, transfusion increased by more than 3-fold among ibuprofen users compared with nonusers (adjusted OR, 3.16; 95% CI, 1.01-9.91), and the upper limit of the 95% CI suggests the difference could be nearly 10 times greater.

Conclusions and Relevance

The risk for sPTH is not increased with use of postoperative ibuprofen but is increased in patients 12 years or older and patients undergoing tonsillectomy with a history of recurrent tonsillitis. Hemorrhage severity is significantly increased with ibuprofen use when using transfusion rate as a surrogate marker for severity.

Children With Sensorineural Hearing Loss And Referral To Early Intervention

OBJECTIVE

Sensorineural hearing loss (SNHL) is identified at a rate of 1-3 per 1,000 newborns in the United States. Timely referral to Early Intervention (EI) services is critical, as early EI referral has been shown to improve outcomes, including speech and language development, social and emotional development, and academic performance. The objective of this study was to determine the rate at which children diagnosed with SNHL at a large tertiary referral center were referred to EI, and, if so, by whom. In addition, we sought to determine the time from the diagnosis of SNHL to the completion of the referral, and what services were received.

DESIGN

Prospective observational study

METHODS

Data were collected by telephone survey and review of the electronic medical record

RESULTS

Children with SNHL were referred to and participated in EI at a high rate. All children in this study (100%) were referred to EI. Most (92%) of the children were referred by 6 months of age, and almost all (98%) participated in EI.

CONCLUSION

At our institution, children with SNHL are being consistently referred to EI, meeting the goals of the Early Hearing Detection and Intervention program. Future outcomes research can now be designed to determine whether achieving these benchmark goals improves children's academic performance, expressive and receptive language skills, and development as compared to age-matched, normal hearing peers.

Clinical practice guideline: tonsillectomy in children

OBJECTIVE

Tonsillectomy is one of the most common surgical procedures in the United States, with more than 530,000 procedures performed annually in children younger than 15 years. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil including its capsule by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Depending on the context in which it is used, it may indicate tonsillectomy with adenoidectomy, especially in relation to sleep-disordered breathing. This guideline provides evidence-based recommendations on the preoperative, intraoperative, and postoperative care and management of children 1 to 18 years old under consideration for tonsillectomy. In addition, this guideline is intended for all clinicians in any setting who interact with children 1 to 18 years of age who may be candidates for tonsillectomy.

PURPOSE

The primary purpose of this guideline is to provide clinicians with evidence-based guidance in identifying children who are the best candidates for tonsillectomy. Secondary objectives are to optimize the perioperative management of children undergoing tonsillectomy, emphasize the need for evaluation and intervention in special populations, improve counseling and education of families of children who are considering tonsillectomy for their child, highlight the management options for patients with modifying factors, and reduce inappropriate or unnecessary variations in care.

RESULTS

The panel made a strong recommendation that clinicians should administer a single, intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. The panel made a strong recommendation against clinicians routinely administering or prescribing perioperative antibiotics to children undergoing tonsillectomy. The panel made recommendations for (1) watchful waiting for recurrent throat infection if there have been fewer than 7 episodes in the past year or fewer than 5 episodes per year in the past 2 years or fewer than 3 episodes per year in the past 3 years; (2) assessing the child with recurrent throat infection who does not meet criteria in statement 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergy/intolerance, periodic fever, aphthous stomatitis, pharyngitis and adenitis, or history of peritonsillar abscess; (3) asking caregivers of children with sleep-disordered breathing and tonsil hypertrophy about comorbid conditions that might improve after tonsillectomy, including growth retardation, poor school performance, enuresis, and behavioral problems; (4) counseling caregivers about tonsillectomy as a means to improve health in children with abnormal polysomnography who also have tonsil hypertrophy and sleep-disordered breathing; (5) counseling caregivers that sleep-disordered breathing may persist or recur after tonsillectomy and may require further management; (6) advocating for pain management after tonsillectomy and educating caregivers about the importance of managing and reassessing pain; and (7) clinicians who perform tonsillectomy should determine their rate of primary and secondary posttonsillectomy hemorrhage at least annually. The panel offered options to recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year or at least 5 episodes per year for 2 years or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and 1 or more of the following: temperature >38.3°C, cervical adenopathy, tonsillar exudate, or positive test for group A β-hemolytic streptococcus.

Phase II trial evaluating imatinib (I) in patients (pts) with anaplastic thyroid carcinoma (ATC)

6057

Background: There is no standard treatment for ATC. Response to doxorubicin ranges between 5–22%; median survival ranges between 3–6 months. Affymetrix gene chip showed PDGFR overexpression in ATC. In p53 mutated/deficient ATC cell lines, c-Abl is overexpressed, and selective inhibition of c-Abl resulted in cytostatic effect. (I) inhibits tyrosine kinase activity of Bcr-Abl and PDGF. We hypothesize that ATC that overexpress PDGFR or Abl will respond to (I). Methods: Pts ≥ 18 years old with histologically confirmed ATC, overexpressing PDGFR or c-Abl by immunohistochemistry who had measurable disease were eligible. Pts must have Zubrod performance status ≤ 1, and adequate hepatic and renal function. Prior chemotherapy, chemoradiation, radiation therapy, or surgery must have been completed at least 28 days prior to registration. (I) was administered at 400mg orally twice daily without drug holiday. Response to treatment was assessed after every 8 weeks. Pts with complete response (CR)/partial responses (PR)/stable disease (SD) were treated until disease progression. The study was terminated early due to poor accrual. Results: From February 2004 to May 2007, eleven pts from our institution were enrolled and were started on (I) (6 men; 5 women) with a median age of 63 years (ranges 53–80). At baseline, 4/11 pts (36%) had locoregional disease, 5/11 pts (45%) had distant metastases, and 2/11 pts (18%) had both. Nine pts had prior chemoradiation, and 7 pts had thyroidectomy. Out of 11 pts, 8 were evaluable for response; 3 were excluded for lack of follow up radiological evaluation. The overall responses at 8 weeks were CR 0/8; PR 2/8 (25%); SD 4/8 (50%); and PD 2/8 (25%). The median time to follow up was 26 months (ranges 23–30 months). The estimate of 6-month progression free survival was 27% (95% CI, 7–54%). The estimate of 6-month overall survival was 46% (95% CI, 17–71%). The most common G3 toxicity was lymphopenia in 45%; other G3 toxicities included edema (27%), anemia (18%), and hyponatremia (18%). There was no G4 or higher or treatment related death. Conclusions: (I) appears to have activity in advanced ATC and is well tolerated. Due to difficulty of accruing pts with a rare malignancy at a single institution, investigation of (I) in ATC may be warranted in a multi-institution setting.

No significant financial relationships to disclose.

Beta cell chromogranin B is partially segregated in distinct granules and can be released separately from insulin in response to stimulation

AIMS/HYPOTHESIS

We investigated, in three beta cell lines (INS-1E, RIN-5AH, betaTC3) and in human and rodent primary beta cells, the storage and release of chromogranin B, a secretory protein expressed in beta cells and postulated to play an autocrine role. We asked whether chromogranin B is stored together with and discharged in constant ratio to insulin upon various stimuli.

METHODS

The intracellular distribution of insulin and chromogranin B was revealed by immunofluorescence followed by three-dimensional image reconstruction and by immunoelectron microscopy; their stimulated discharge was measured by ELISA and immunoblot analysis of homogenates and incubation media.

RESULTS

Insulin and chromogranin B, co-localised in the Golgi complex/trans-Golgi network, appeared largely segregated from each other in the secretory granule compartment. In INS-1E cells, the percentage of granules positive only for insulin or chromogranin B and of those positive for both was 66, 7 and 27%, respectively. In resting cells, both insulin and chromogranin B were concentrated in the granule cores; upon stimulation, chromogranin B (but not insulin) was largely redistributed to the core periphery and the surrounding halo. Strong stimulation with a secretagogue mixture induced parallel release of insulin and chromogranin B, whereas with 3-isobutyl-1-methylxantine and forskolin +/- high glucose release of chromogranin B predominated. Weak, Ca(2+)-dependent stimulation with ionomycin or carbachol induced exclusive release of chromogranin B, suggesting a higher Ca(2+) sensitivity of the specific granules.

CONCLUSIONS/INTERPRETATION

The unexpected complexity of the beta cell granule population in terms of heterogeneity, molecular plasticity and the differential discharge, could play an important role in physiological control of insulin release and possibly also in beta cell pathology.

Safety, tolerability and efficacy of sublingual allergoid immunotherapy with a 4-day shortened build-up phase

BACKGROUND

Sublingual specific immunotherapy (SLIT) with monomeric allergoid has shown to be safe and effective the studies performed so far. The build-up phase, however, is rather time consuming mainly if performed with the conventional schedule of 14 weeks.

AIMS OF STUDY

We evaluated the possibility of shortening and simplifying this phase, through a new build-up scheme of only 4 days, as well as the persistence of the allergoid SLIT efficacy after 12 months.

METHODS

Thirty-nine patients (26 M, 13 F, mean age 20.5 years, range 6-49) with a history of moderate/severe rhinitis with or without mild asthma due to perennial and/or seasonal allergens entered the study. The posological schedule, adopting only 1,000 AU tablets, was the following: 1/2 tablet the 1st day; 1/2 table twice the second day; 1/2 table plus 1 table the 3rd day, 1 tablet twice the 4th day; 1 tablet twice weekly from the 5th to the 365th day (maintenance therapy).

RESULTS

Only two mild adverse reactions occurred during the initial phase which disappeared with the prosecution of the treatment. During the maintenance therapy no adverse event was observed. Symptoms improved consistently and drug consumption was reduced in most of the patients.

CONCLUSIONS

The 4-day shortened build-up phase resulted to be safe, well tolerated and effective, already after one year of treatment.

Proteomics-based identification of protein gene product 9.5 as a tumor antigen that induces a humoral immune response in lung cancer

We used a proteomic approach to identify proteins that commonly induce an antibody response in lung cancer. Sera from 64 newly diagnosed patients with lung cancer, 99 patients with other types of cancer, and 71 noncancer controls were analyzed for antibody-based reactivity against lung adenocarcinoma proteins resolved by two-dimensional PAGE. Unlike controls, autoantibodies against a protein identified by mass spectrometry as protein gene product 9.5 (PGP 9.5) were detected in sera from 9 of 64 patients with lung cancer. Circulating PGP 9.5 antigen was detected in sera from two additional patients with lung cancer, without detectable PGP 9.5 autoantibodies. PGP 9.5 is a neurospecific polypeptide previously proposed as a marker for non-small cell lung cancer, based on its expression in tumor tissue. Using A549 lung adenocarcinoma cell line, we have demonstrated that PGP 9.5 was present at the cell surface, as well as secreted. Thus, the findings of PGP 9.5 antigen and/or antibodies in serum of patients with lung cancer suggest that PGP 9.5 may have utility in lung cancer screening and diagnosis.

Hippocampal injections of amyloid beta-peptide 1-40 impair subsequent one-trial/day reward learning

The injection of amyloid beta-peptide (Abeta) into rat CNS has been reported to induce cellular neuropathology. The present study investigated whether multiple intrahippocampal injections of Abeta 1-40 would impair one-trial/day reward learning 14 days later. Twenty-four male Sprague-Dawley rats, 3-4 months old, were injected with either Abeta 1-40 or distilled water into seven hippocampal sites bilaterally. Ten rats received 3 nmol Abeta 1-40 in 2 microl of distilled water per injection site, while 14 rats received distilled water alone. Following a 9-day recovery period, rats were gradually food deprived to 82% of their initial body weight. Fourteen days after the intrahippocampal injection, all rats received an initial training trial and three subsequent daily retention trials. Rats receiving Abeta 1-40 were significantly impaired on the second retention trial in terms of accuracy (number of unbaited alleys entered) and on the second and third retention trials in terms of speed (reciprocal of latency to reward). Histological analysis showed that Abeta 1-40 injections produced significant neuronal loss and gliosis. Abeta 1-40 immunoreactivity persisted locally at the injection site and in macrophages 2 weeks following the hippocampal injections. These effects appear to be sequence-specific; rats receiving Abeta 1-42 with a scrambled peptide sequence did not differ significantly from rats receiving distilled water alone in retention of the learning task or degree of histological damage.

RNA as a drug target: methods for biophysical characterization and screening

RNA folds into complex structures that can interact specifically with effector proteins. These interactions are essential for various biological functions. In order to discover small molecules that can affect important RNA-protein complexes, a thorough analysis of the thermodynamics and kinetics of RNA-protein binding is required. This can facilitate the formulation of high-throughput screening strategies and the development of structure-activity relationships for compound leads. In addition to traditional methods, such as filter binding, gel mobility shift assay and various fluorescence techniques, newer methods such as surface plasmon resonance and mass spectrometry are being used for the study of RNA-protein interactions.

Identification of AUF-1 ligands reveals vast diversity of early response gene mRNAs

Cell activation is associated with diverse and widespread changes in gene expression at both the transcriptional and post-transcriptional levels. AUF1 is a recently described cytoplasmic protein which likely participates in the post-transcriptional regulation (PTR) of AU-rich (ARE) mRNAs including those coding for cytokines and proto-oncogenes. Individual mRNAs subject to AUF1-mediated PTR can be predicted if AREs are present or the mRNA in question interacts in vitro or in vivo with AUF1. However, there are few, if any, general approaches for characterizing the overall repertoire of mRNAs subject to PTR by AUF1. In an effort to identify these mRNAs, we incubated total mRNA from mitogen-activated peripheral blood mono-nuclear cells (PBMCs) with AUF1 in vitro. AUF1-mRNA complexes were retarded on membranes, bound mRNAs eluted with high salt, and either used to generate a cDNA library or rebound to AUF1 a second or third time prior to elution and cDNA library construction. We have obtained partial nucleotide sequences from 130 clones which shows that the AUF1 selected libraries are rich in mRNAs containing 3' untranslated region AREs including a large number of early response gene cDNAs. As a test of the validity of this method, we also show that a randomly selected, novel mRNA contained in the library is stabilized upon cell activation.

(2S,4R)-4-methylglutamic acid (SYM 2081): a selective, high-affinity ligand for kainate receptors

Glutamic acid activates ionotropic glutamate receptors that mediate excitatory transmission in the central nervous system. The introduction of a methyl group at position 4 of glutamic acid imparts selectivity for kainate receptors, relative to other (N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) ionotropic glutamate receptors. Among the stereoisomers of 4-methylglutamic acid, the potency of the (2S,4R)-isomer (SYM 2081) to inhibit [3H]kainic acid binding to both wild-type (rat forebrain) and recombinant (GluR6) kainate receptors (IC50 values of approximately 32 and 19 nM, respectively) was comparable to that of kainic acid (IC50 values of approximately 13 and 28 nM, respectively). SYM 2081 was approximately 800- and 200-fold less potent as an inhibitor of radioligand binding to wild-type (rat forebrain) alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and N-methyl-D-aspartate receptors, respectively. Preexposure of human embryonic kidney 293 cells stably expressing GluR6 receptors to low concentrations of SYM 2081 (30-300 nM) resulted in a reversible blockade of the rapidly desensitizing currents produced by kainate application. At higher concentrations, SYM 2081 (EC50 of approximately 1 microM) elicited kainate-like, rapidly desensitizing, inward currents. Pretreatment of recombinant GluR6 receptors with concanavalin A both abolished the effect of SYM 2081 to block kainate-induced currents and revealed nondesensitizing currents induced by SYM 2081 alone. The latter observations provide strong support for the hypothesis that SYM 2081 blocks kainate-induced currents through a process of agonist-induced desensitization. SYM 2081 also activated alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor currents in primary cultures of cerebral cortex and, consistent with data obtained by radioligand binding, was approximately 5-fold less potent than kainate (EC50 values of 325 and 70 microM, respectively) in this measure. SYM 2081 is a high-affinity, selective, kainate agonist that may prove useful both as a probe to examine the physiological functions of kainate receptors and as the prototype of a novel class of therapeutic agents.

Sensitization to cockroach in Italy: a multicentric study

The prevalence of sensitization to cockroach (CR) was evaluated by skin prick test (SPT) in 1299 patients consecutively referred for rhinitis and asthma to five allergy centers in northern, central, and southern Italy. In patients with positive SPT to CR, an SPT with D. pteronyssinus extract was made. RAST inhibition was performed with pooled sera of subjects with positive SPT and RAST of at least Class 3 for CR and D. Pteronyssinus, to assess the cross-reactivity between these two allergenic sources. The protein content of allergen extracts was assayed by isoelectric focusing (IEF). A total of 170 patients (13%) had a positive SPT with CR extract, and 133 of them (78.2%) were also positive for D. pteronyssinus. RAST inhibition showed a cross-reactivity between CR and D. pteronyssinus, and IEF detected in the extracts employed a series of bands focusing at the same pI of CR and D. pteronyssinus relevant allergens. Therefore, the prevalence of sensitization to CR in the population studied, corresponding to 13%, suggests that CR extract might be added to standard SPT panels for respiratory allergy. However, the cross-reactivity with D. pteronyssinus calls for careful evaluation of the clinical importance of this sensitization.

Cloning of the cDNA for the human NMDA receptor NR2C subunit and its expression in the central nervous system and periphery

Several overlapping cDNA clones containing 3995 nucleotides of the human 2C NMDA receptor subunit (NR2C) were isolated from human hippocampal and cerebellar cDNA libraries. The nucleic acid sequence of the overlapping cDNA clones displays 85% identity to that of rat NR2C. The predicted protein sequence is 1233 amino acids long and has 88% identity to the amino acid sequence of the rat NR2C, Northern blot analysis has demonstrated a wide distribution pattern of the NR2C transcript in the brain. While the predominant expression is in the cerebellum, as observed in the rat, readily detectable levels are present in the hippocampus, amygdala, caudate nucleus, corpus callosum, subthalamic nuclei and thalamus. NR2C was also detected in the heart, skeletal muscle and pancreas. Distribution of the mouse NR2C NMDA receptor subunit homologue was investigated in mouse brain by in situ hybridization histochemistry using exonic genomic probes. Expression of the transcript was principally in the cerebellum, but is also detected in the hippocampus, dentate gyrus, thalamic and subthalamic nuclei, vestibular nuclei and olfactory bulb. These results demonstrate a widespread expression pattern of the NR2C gene, both in the CNS and in the periphery.

Riedel's thyroiditis: treatment with tamoxifen

BACKGROUND

Riedel's thyroiditis is an often disabling disease with clinical and histologic similarity to several other fibrous inflammatory disorders. Surgical treatment alone is often unsatisfactory in permanently alleviating airway compression, dysphagia, neck immobility, pain, or chronic fatigue syndrome. Investigation of drugs shown to be of benefit in the treatment of related fibrous disorders in which hormonal factors or inflammatory deregulation appear to be important is indicated. Tamoxifen has not been previously used in the treatment of Riedel's thyroiditis.

METHODS

Four patients with clinical and histologic diagnoses of Riedel's thyroiditis were evaluated before and after treatment with tamoxifen. Each had progressive symptomatic disease of 3 to 16 years' duration despite one or more surgical procedures and steroid therapy. Subjective improvement was noted in all cases, and objective changes were confirmed by periodic physical and computed tomographic examinations.

RESULTS

Patients have been monitored for 1 to 4 years with subjective improvement in 100% and objective disease regression ranging from 50% to 100% in all patients. One patient had complete regression within 6 months, and another had more than 50% regression within 3 months. All have returned to predisease activity levels. There were no significant side effects of the therapy.

CONCLUSIONS

Tamoxifen has proved to be the most effective drug therapy available for managing Riedel's thyroiditis. Our studies suggest that this is unrelated to antiestrogen activity. Tamoxifen's effectiveness may be caused by a mechanism by which it stimulates the release of transforming growth factor-beta, which may inhibit the fibroblastic proliferation characteristic of Riedel's thyroiditis.

Cytotoxic effects of kainate ligands on HEK cell lines expressing recombinant kainate receptors

Exposure of neurons either for prolonged periods of time or to high concentrations of excitatory amino acids (EAA), such as glutamate, results in neuronal death. Kainate also causes cell toxicity through the glutamate receptors. However, it is unclear whether the kainate receptor itself mediates any of the toxic responses. In the present study, HEK cells expressing the GluR6 +/- KA2 receptor subunit(s) were studied for their susceptibility to toxicity through the kainate receptor by kainate ligands. The natural ligand, glutamate, did not result in toxicity to the recombinant cell lines over that observed with the untransfected HEK cells, whereas kainate produced a 2-3-fold increase in LDH in both the HEK/GluR6 (ANOVA, P = 0.0001) and HEK/GluR6 + KA2 (ANOVA, P = 0.0002) cell lines following treatment with various dosages, but did not affect the HEK cells. Similar 2-3-fold increases in LDH activity were detected in both recombinant cell lines following treatment with 100 nM of SYM2081 ((2S,4R)-4-methylglutamic acid), a dose at which agonistic activity is elicited. The rank order potencies for eliciting toxicity are consistent with the previously reported EC50 values (SYM2081 > kainate > > > glutamate). Surprisingly, the kainate antagonist, NBQX, was the most toxic of the compounds tested although it had an affinity for the kainate receptor similar to glutamate. Treatment with as little as 10 nM elicited a dramatic increase in toxicity (6-10-fold) in the recombinant cell lines. At 1 microM, NBQX was significantly more toxic (Fisher PLSD, P < 0.05) than any of the other compounds tested. Thus, it appears that cell toxicity can be mediated via kainate receptor through two independent mechanisms: activation and blockage of the kainate receptor.

AUUUA-specific mRNA binding proteins in astrocytes

Binding of ribonucleoproteins to specific regions of mRNA can alter mRNA stability. This level of posttranscriptional regulation has been shown to play a major role in gene expression of eukaryotic cells. This process involves the binding of ribonucleoproteins to specific region(s) of unstable, rapidly degrading mRNAs such as those found in various cytokines, lymphokines, and oncogenes, thereby increasing the mRNA's stability. In many instances the instability of the mRNA has been mapped to an AU-rich motif in the 3' untranslated region. We transcribed RNA molecules containing four reiterations of an AUUUA motif, and demonstrated with RNA- band shift experiments that the AUUUA motif complexes with phosphorylated AUUUA-specific 43-47 kDa mRNA binding protein(s) found in the cytosol of both rat brain and cultured rat astrocytes.

Differential immunohistochemical detection of transforming growth factor alpha, amphiregulin and CRIPTO in human normal and malignant breast tissues

The expression of growth factors, such as transforming growth factor alpha (TGF alpha), amphiregulin (AR) and CRIPTO, a type-1 tyrosine-kinase growth factor receptor (erbB-2), and a tumor-suppressor gene (p53), that have been implicated in the development and/or the progression of breast cancer, was evaluated by immunohistochemistry in 100 human primary infiltrating breast carcinomas (IBC). AR and CRIPTO immunoreactivity was also assessed in 55 human breast ductal carcinomas in situ (DCIS). Within the 100 IBC, 80, 50, 73, 17, and 34 tumors expressed moderate to high levels of TGF alpha, AR, CRIPTO, erbB-2, and p53 respectively. In addition, AR and CRIPTO immunoreactivity were found in 11 and in 26 out of 55 DCIS respectively. In contrast, only 4, 3, and 2 out of 10 normal mammary-gland samples were weakly positive for TGF alpha, AR, and CRIPTO expression, respectively, whereas none was positive for erbB-2 or p53. Within the 100 IBC, expression of erbB-2 significantly correlated with high histologic and nuclear grading, with high growth fraction, and with estrogen-receptor (ER)- and progesterone-receptor (PgR)-negative tumors. A statistically significant correlation was also observed between p53 expression and high histologic grading, high growth fraction, and PgR-negative tumors. In contrast, no significant correlations were found between TGF alpha, AR, and CRIPTO immunoreactivity and various clinicopathological parameters, with the exception of a positive correlation between TGF alpha and ER expression. These data demonstrate that TGF alpha, AR, and CRIPTO expression are significantly increased in malignant mammary epithelium relative to normal epithelium. In particular, the differential expression of CRIPTO may serve as a potential tumor marker for breast carcinogenesis.

Differential immunohistochemical detection of transforming growth factor alpha, amphiregulin and CRIPTO in human normal and malignant breast tissues

The expression of growth factors, such as transforming growth factor alpha (TGF alpha), amphiregulin (AR) and CRIPTO, a type-1 tyrosine-kinase growth factor receptor (erbB-2), and a tumor-suppressor gene (p53), that have been implicated in the development and/or the progression of breast cancer, was evaluated by immunohistochemistry in 100 human primary infiltrating breast carcinomas (IBC). AR and CRIPTO immunoreactivity was also assessed in 55 human breast ductal carcinomas in situ (DCIS). Within the 100 IBC, 80, 50, 73, 17, and 34 tumors expressed moderate to high levels of TGF alpha, AR, CRIPTO, erbB-2, and p53 respectively. In addition, AR and CRIPTO immunoreactivity were found in 11 and in 26 out of 55 DCIS respectively. In contrast, only 4, 3, and 2 out of 10 normal mammary-gland samples were weakly positive for TGF alpha, AR, and CRIPTO expression, respectively, whereas none was positive for erbB-2 or p53. Within the 100 IBC, expression of erbB-2 significantly correlated with high histologic and nuclear grading, with high growth fraction, and with estrogen-receptor (ER)- and progesterone-receptor (PgR)-negative tumors. A statistically significant correlation was also observed between p53 expression and high histologic grading, high growth fraction, and PgR-negative tumors. In contrast, no significant correlations were found between TGF alpha, AR, and CRIPTO immunoreactivity and various clinicopathological parameters, with the exception of a positive correlation between TGF alpha and ER expression. These data demonstrate that TGF alpha, AR, and CRIPTO expression are significantly increased in malignant mammary epithelium relative to normal epithelium. In particular, the differential expression of CRIPTO may serve as a potential tumor marker for breast carcinogenesis.

Stable expression and pharmacological properties of the human alpha 7 nicotinic acetylcholine receptor

The alpha 7 neuronal nicotinic acetylcholine receptor subtype forms a Ca(2+)-permeable homooligomeric ion channel sensitive to alpha-bungarotoxin in Xenopus oocytes. In this study, we have stably and functionally expressed the human alpha 7 cDNA in a mammalian cell line, HEK-293 and examined its pharmacologic properties. [125I] alpha-Bungarotoxin bound to transfected cells with a Kd value of 0.7 nM and a Bmax value of 973 pmoL/mg protein. No specific binding was detected in untransfected cells. Specific binding could be displaced by unlabeled alpha-bungarotoxin (Ki = 0.5 nM) and an excellent correlation was observed between binding affinities of a series of nicotinic cholinergic ligands in transfected cells and those in the human neuroblastoma IMR-32 cell line. Additionally, cell surface expression of alpha 7 receptors was detected by fluorescein isothiocyanate-conjugated alpha-bungarotoxin in transfected cells. Whole cell currents sensitive to blockade by alpha-bungarotoxin, and with fast kinetics of activation and inactivation, were recorded from transfected cells upon rapid application of (-)-nicotine or acetylcholine with EC50 values of 49 microM and 155 microM respectively. We conclude that the human alpha 7 subunit when expressed alone can form functional ion channels and that the stably transfected HEK-293 cell line serves as a unique system for studying human alpha 7 nicotinic receptor function and regulation, and for examining ligand interactions.

Cloning and transient expression of genes encoding the human alpha 4 and beta 2 neuronal nicotinic acetylcholine receptor (nAChR) subunits

Partial cDNA clones generated by RT-PCR were used as probes to clone the cDNAs encoding the human alpha 4 and beta 2 neuronal nicotinic acetylcholine receptor (nAChR) subunits. The 2.1-kb alpha 4 cDNA shows 84 and 76% identity to the rat and chicken cDNA sequences, respectively. The deduced amino-acid sequence shares 89 and 84% similarity, respectively, with the corresponding rat and chicken proteins, with most of the divergence occurring in the cytoplasmic domain. The 1721-nucleotide beta 2 sequence was identical to the human beta 2 sequence previously reported. Transfection of the alpha 4 and beta 2 clones into HEK293 cells resulted in the formation of binding sites that display high affinity towards [3H] cytisine, a characteristic of the alpha 4 beta 2 subtype produced in vivo.

Impairment in mitochondrial cytochrome oxidase gene expression in Alzheimer disease

Brains from 5 patients with Alzheimer's disease (AD) showed a 50%-65% decrease in mRNA levels of the mitochondrial-encoded cytochrome oxidase (COX, a marker of oxidative metabolism) subunits I and III in the middle temporal association neocortex, but not in the primary motor cortex, as compared to 5 control brains. The amount of mitochondrial-encoded 12S rRNA was not altered, nor was the amount of nuclear-encoded lactate dehydrogenase B mRNA (a marker of glycolytic metabolism). These data suggest that the decrease in COX I and III subunits mRNA in affected brain regions may contribute to reduced brain oxidative metabolism in AD.

Nicotine effects on the regulation of amyloid precursor protein splicing, neurotrophin and glucose transporter RNA levels in aged rats

It has been reported that an inverse relationship exists between nicotine intake and the incidence of Alzheimer's Disease (AD). Although nicotine has been reported to induce c-fos, in the present study it was shown that this induction does not alter the accumulation of a number of transcripts associated with AD. Altered splicing patterns of Amyloid Precursor Protein (APP) and changes in neurotrophin and glucose transporter expression have been implicated in AD and behavioral deficits in rats. The effects of subacute administration of nicotine (12 mg/ml at 2.3 microliters/hr for 14 days) on the abundance levels of APP, glucose transporter (GLUT) and neurotrophin transcripts were determined by rtPCR in the hippocampus, cortex, and striatum of aged (22-24 months) male Wistar rats. No significant differences between saline and nicotine infused rats were detected for APP abundance levels or ratio of the various isoforms. However, both groups had a higher level of APP transcripts containing the Kunitz Protease Inhibitor (KPI) domain in the hippocampus than in either the cortex or striatum. The mean percentages of APP 695 for the two groups were 75% in the hippocampus and 82 and 81% in the cortex and striatum, respectively (P < 0.01). No changes in the abundance of GLUT1, GLUT3, nerve growth factor (NGF) or brain derived neurotrophic factor (BDNF) transcripts were detected. However, since both APP and GLUT1 are thought to be regulated post-transcriptionally, the present results do not rule out a change at the protein level. Further work will be required to determine whether nicotine can influence the expression of these proteins which affect neuronal function.

Similarities between beta amyloid peptides 1-40 and 40-1: effects on aggregation, toxicity in vitro, and injection in young and aged rats

Peptides corresponding to the first 40 amino acids of beta amyloid peptide (beta 1-40) and the reverse sequence (beta 40-1) were synthesized, purified, and compared for their ability to aggregate and cause toxicity in vitro to human neuroblastoma cells (SH-SY5Y), as well as for effects following injection into young or aged rats. Aggregation of both peptides produced similar sedimentation velocity profiles and resulted in significant toxicity in vitro with no observable differences between beta 1-40 and beta 40-1. In addition, when injected into the cortex of young rats, beta 1-40 was more toxic than beta 40-1 although both resulted in significant lesions. However, in aged rats the two peptides resulted in lesions of similar size. Alz 50 staining and abnormal neurites were associated with both beta 1-40 and beta 40-1 lesions; however, no evidence of plaques or tangles was found in either age group. While both peptides were toxic in vitro, only beta 1-40 elicited Alz 50 staining of SH-SY5Y cells. Electron microscopic examination of beta 1-40 and beta 40-1 aggregates showed that beta 1-40 formed fibrillar structures whereas beta 40-1 resulted in amorphous particles. Thus, although both peptides were toxic to cultured cells and aged rats, the toxicities may have resulted from different mechanisms.

[Adenocarcinoma of the cecal appendix]

The authors report one rare case of primary adenocarcinoma of the vermiform appendix. The patient, an 83 year old female, presented with a non-pathognomonic symptomatology; diagnosis was made postoperatively. Surgery consisted of appendicectomy. The patient, due to her poor general condition, died three days after surgery for cardiocirculatory complications. In the light of the very rare case published in the literature, some diagnostic, anatomic-clinical, therapeutic and prognostic aspects of this rare tumor are discussed.

Quantitative reverse transcriptase-polymerase chain reaction of glucose transporter 1 mRNA levels in rat brain microvessels

We investigated the usefulness of reverse transcriptase-polymerase chain reaction (RT-PCR) to quantify glucose transporter 1 (GLUT1) mRNA in cerebral microvessels. The technique was validated using an in vitro-transcribed RNA fragment (riboprobe) of partial 3' noncoding sequence of rat brain GLUT1 gene. A known amount of the riboprobe was reverse-transcribed to cDNA (target DNA). PCR primers were made to amplify a 292-bp fragment of the target DNA. The 5' primer was end labeled with 32P. An oligonucleotide of 100 bp containing the same sequences as the first 30 and the last 70 bases of the 292-bp fragment of the target DNA was synthesized and used as competitive DNA. The target DNA was coamplified with increasing amounts of competitive DNA using the same two primers. The ratio of radioactivity between amplified products of the target DNA (292-bp fragment) and the competitive DNA (100-bp fragment) was determined quantitatively after separation by gel electrophoresis and radioactivity counting. This method gave an accurate estimation of the amount of the riboprobe in the reaction and a 2- to 5-fold change in the amounts could be detected. By this method, the mean amount of GLUT1 mRNA from purified rat brain microvessels was estimated to be 1.5 +/- 0.1 x 10(-6) ng/ng total RNA. This value was about 10-fold higher than that in rat cell line PC12.

Altered levels and splicing of the amyloid precursor protein in the adult rat hippocampus after treatment with DMSO or retinoic acid

Alzheimer's disease and cognitive impairment in rats has been associated with an increase in the percentage of amyloid precursor protein (APP) containing the KPI domain. It has recently been reported that retinoic acid (RA) is capable of increasing the levels and altering the splicing ratio of APP in cultured SH-SY5Y cells. The effects of peripherally administered RA (64 or 640 micrograms/kg; i.p.; q.d.) on the abundance of APP, the ratio of the three major isoforms, and the relative abundance of nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) were determined by rtPCR in the hippocampus of aged rats. Corresponding changes in choline acetyltransferase (ChAT) activity were also measured. Vehicle (DMSO) treated rats exhibited a 2 x (P < 0.01) increase in total APP and an 8 x (P < 0.001) decrease in the cyclophilin transcript. In addition, DMSO increased the percentage of APP 695 from 89% in saline treated rats to 94%. Treatment of RA in DMSO decreased the accumulation of total APP relative to cyclophilin at both the low (6.4 x; P < 0.01) and high (8 x; P < 0.05) dosages when compared to DMSO treated rats. Furthermore, the level of APP-695 decreased to 82% with low dosage of RA and 75% at high dosage of the total APP transcripts. No significant change in either NGF, NT-3, or BDNF transcripts were observed following low or high dosage RA administration relative to cyclophilin RNA nor was a change in ChAT activity detected at either of the dosages tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Thyroid hormone regulation of NGF, NT-3 and BDNF RNA in the adult rat brain

The effects of peripherally administered thyroid hormone (TH; 500 micrograms/kg; i.p.; q.d.) on the relative abundances of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) RNA were determined by rtPCR in the cortex and hippocampus of young adult rats. Corresponding changes in choline acetyltransferase (ChAT) activity were measured since NGF and BDNF have been shown to enhance the expression of this marker enzyme of central cholinergic pathways. Abundance levels of NGF and NT-3, relative to cyclophilin (cycl), were increased significantly (+50%, P < 0.05) in the hippocampus following TH treatment. Despite enhanced abundance of NGF in the hippocampus, ChAT activity was unchanged, whereas ChAT activity was modestly increased by 28% in the cortex without corresponding changes in NGF, NT-3 or BDNF. These results demonstrate that TH administration is capable of inducing the accumulation of NT-3, in addition to NGF but that the induction levels of RNA cannot be directly correlated with responsivity of the cholinergic system as measured by ChAT activity.

Differential expression of cytochrome oxidase (COX) genes in different regions of monkey brain

A frontal pole cDNA library from monkey (Macaca mulatta) brain was screened to identify mRNAs that are expressed more in frontal pole as compared to primary visual cortex. Three cDNA clones, whose greater expression was confirmed by Northern blot analysis, were identified as cytochrome oxidase (COX) subunits I, II, and III (COX I, II, and III). Each clone showed higher levels of mRNA in the frontal pole, dorsal lateral prefrontal cortex, and hippocampus than in the primary visual or somatosensory cortices. COX histochemistry of prefrontal, visual, and somatosensory cortical regions demonstrated heterogeneous distributions, with highest activity in dendrite-rich neuropil of the cortex. A laminar distribution of COX mRNA expression also was demonstrated with in situ hybridization. mRNA was detected in cell bodies and in apical dendrites. These results indicate region specific differences in the distribution of COX activity and in the corresponding mRNA for three of its subunits within the monkey brain. Such differences may be related to differences in the distribution of neuropil as compared with cell bodies among the brain regions studied, and may be relevant to selective vulnerability in Alzheimer's disease.

Expression of Alu and 7SL RNA in Alzheimer's and control brains

We investigated whether changes in expression of RNA polymerase III (pol III) or heterodisperse RNA polymerase II (pol II) transcripts hybridizing to Alu could be detected in Alzheimer's disease (AD). RNA samples obtained from AD and control brain tissues were examined by Northern analysis for Alu and 7SL RNA expression. All RNA samples contained a prominent band of approximately 300 nucleotides which corresponds to 7SL RNA, the Alu-homologous RNA component of the signal recognition particle. In addition, three small (i.e. less than 300 nucleotide) 7SL/Alu-hybridizing transcripts were detected. The two larger of the low molecular weight transcripts hybridized preferentially to the 7SL RNA probe, while the smallest transcript hybridized to the Alu probe. These transcripts and the heterodisperse RNA were variable in quantity and displayed a lack of correlation with AD.

Nucleotide sequence of the cDNA encoding the common alpha subunit of the chicken pituitary glycoprotein hormones

Recombinant cDNA clones that encode the alpha subunit of the chicken pituitary glycoprotein hormones were isolated from a pituitary library. The longer of the two cDNA clones that were sequenced was 754 bp in length. It contained 81 nucleotides of the 5'-untranslated region (UTR), an open-reading frame of 360 bp that encoded a 24 amino acid leader polypeptide sequence as well as the 96 amino acid mature alpha subunit, and 268 nucleotides of the 3'-UTR, followed by a 45 bp poly(A) tract. There was 69-79% homology between the nucleotide sequence of the coding region for the chicken and mammalian alpha-subunit cDNAs. Northern blot analysis revealed that the steady-state levels of an approximately 800 bp alpha-subunit specific transcript increased quantitatively when dispersed chicken pituitary glands were treated in culture with chicken gonadotrophin-releasing hormone-I.