Clinical Manifestations of Recurrent Parotid Pleomorphic Adenoma

Objectives. This study was undertaken to confirm the clinical characteristics of recurrent pleomorphic adenoma (RPA), and to identify those factors that affect the development of malignant transformation (MT) from RPA. Methods. The medical records of 270 patients, who were operated upon for parotid PA, were retrospectively reviewed. The pathologic specimens of a selected series of 23 patients were reviewed for histologic subtype and microscopic multi-nodularity. Results. Mean age of initial operation in RPA without MT (RPA(-MT)) group was significantly lower than that of primary PA group. Mean age of the revision operation in RPA with MT (RPA(+MT)) group was significantly greater than that of RPA(-MT) group. Mean interval from operation to recurrence shortened after each revision operation. The risk of MT and additional recurrence increased significantly with recurrence. In RPA(-MT) group tumor recurrence occurred in 21.4% of patients despite a clear resection margin. Conclusion. The risk factors for MT may be an age of over 45 yr and multiple recurrences. However, younger patients are more at risk of recurrence. A clear resection margin cannot guarantee a cure in RPA, and it seems that parotid pleomorphic adenomas slowly gain malignant characteristics after repeated recurrences.SUH MW, 2005, KOREAN J HEAD NECK O, V21, P146HANNA EY, 2005, CUMMINGS OTOLARYNGOL, P1348Ghosh S, 2003, CLIN OTOLARYNGOL, V28, P262Glas AS, 2002, CANCER, V94, P2211, DOI 10.1002/cncr.10445Glas AS, 2001, HEAD NECK-J SCI SPEC, V23, P311BRADLEY PJ, 2001, CURR OPIN OTOLARYNGO, V9, P100Carew JF, 1999, OTOLARYNG HEAD NECK, V121, P539Junquera L, 1999, HEAD NECK-J SCI SPEC, V21, P652Hancock BD, 1999, ANN ROY COLL SURG, V81, P299Bankamp DG, 1999, LARYNGO RHINO OTOL, V78, P77Hoorweg JJ, 1998, EUR J SURG ONCOL, V24, P452Henriksson G, 1998, CANCER, V82, P617Laskawi R, 1998, BRIT J ORAL MAX SURG, V36, P48Klijanienko J, 1997, HEAD NECK-J SCI SPEC, V19, P629Leverstein H, 1997, EUR ARCH OTO-RHINO-L, V254, P313SunardhiWidyaputra S, 1995, PATHOL RES PRACT, V191, P1186PHILLIPS PP, 1995, ANN OTO RHINOL LARYN, V104, P100BUCHMAN C, 1994, LARYNGOSCOPE, V104, P1231NATVIG K, 1994, HEAD NECK-J SCI SPEC, V16, P213JACKSON SR, 1993, J LARYNGOL OTOL, V107, P546MCGREGOR AD, 1988, BRIT J PLAST SURG, V41, P177FEE WE, 1978, LARYNGOSCOPE, V88, P265SEIFERT G, 1976, HNO, V24, P415NAEIM F, 1976, ARCH PATHOL LAB MED, V100, P271FRAZELL EL, 1954, CANCER, V7, P637

The Clinical Features and Risk Factors of Subglottic Cysts in Children: A Clinical Experience Using the Spontaneous Respiration Technique

Objectives Subglottic cysts (SGCs) are a rare cause of respiratory distress resulting from upper airway obstruction in infants and young children. Risk factors other than prematurity with a history of endotracheal intubation have not yet been well elucidated. Therefore, we aimed to describe the clinical features and analyze the risk factors of SGCs. Methods We conducted a retrospective review of medical records of pediatric patients who underwent marsupialization for SGCs between January 2017 and March 2022. These records were then compared with those of controls with a history of neonatal intubation, with a case-to-control ratio of 1:3. Results Eleven patients (eight boys and three girls) diagnosed with SGCs and 33 control patients (26 boys and seven girls) were included. All patients had a history of premature birth and neonatal intubation. Symptoms of SGCs appeared at a mean age of 8.2 months (range, 1–14 months) after extubation. The mean duration of intubation was 21.5 days (range, 2–90 days), and the intubation period was longer in patients with SGCs than in controls (21.5±24.8 days vs. 5.3±7.1 days; P<0.001). Furthermore, gestational age (28.3±4.2 weeks vs. 33.8±4.4 weeks; P=0.001) and birth weight (1,134.1±515.1 g vs. 2,178.2±910.1 g; P=0.001) were significantly lower in patients with SGCs than in controls. Multivariable analysis identified the intubation period as an independent risk factor. Conclusion This study showed that gestational age, birth weight, and the intubation period were significantly associated with the development of SGCs. Pediatric patients presenting with progressive dyspnea who have the corresponding risk factors should undergo early laryngoscopy for the differential diagnosis of SGC

Selective Delivery of a Therapeutic Gene for Treatment of Head and Neck Squamous Cell Carcinoma Using Human Neural Stem Cells

ObjectivesBased on studies of the extensive tropism of neural stem cells (NSCs) toward malignant brain tumor, we hypothesized that NSCs could also target head and neck squamous cell carcinoma (HNSCC) and could be used as a cellular therapeutic delivery system.MethodsTo apply this strategy to the treatment of HNSCC, we used a human NSC line expressing cytosine deaminase (HB1.F3-CD), an enzyme that converts 5-fluorocytosine (5-FC) into 5-fluorouracil (5-FU), an anticancer agent. HB1. F3-CD in combination with 5-FC were cocultured with the HNSCC (SNU-1041) to examine the cytotoxicity on target tumor cells in vitro. For in vivo studies, an HNSCC mouse model was created by subcutaneous implantation of human HNSCC cells into athymic nude mice. HB1.F3-CD cells were injected into mice using tumoral, peritumoral, or intravenous injections, followed by systemic 5-FC administration.ResultsIn vitro, the HB1.F3-CD cells significantly inhibited the growth of an HNSCC cell line in the presence of the 5-FC. Independent of the method of injection, the HB1.F3-CD cells migrated to the HNSCC tumor, causing a significant reduction in tumor volume. In comparison to 5-FU administration, HB1.F3-CD cell injection followed by 5-FC administration reduced systemic toxicity, but achieved the same level of therapeutic efficacy.ConclusionTransplantation of human NSCs that express the suicide enzyme cytosine deaminase combined with systemic administration of the prodrug 5-FC may be an effective regimen for the treatment of HNSCC

Injection laryngoplasty of human adipose-derived stem cell spheroids with hyaluronic acid-based hydrogel improves the morphological and functional characteristics of geriatric larynx

As the geriatric population increased, the need of treatment for laryngeal atrophy and dysfunction increased. This study was performed to evaluate the effects of injection of human adipose-derived stem cell (hASC) spheroid-loaded catechol-conjugated hyaluronic acid (HA-CA) hydrogel on therapeutic rejuvenation of the geriatric larynx. Stem cell spheroids with hyaluronic acid-based hydrogel were injected into the laryngeal muscles of 18-month-old Sprague–Dawley rats. The effects of hASC spheroids were examined in the following four groups: SHAM, injected with PBS; GEL, injected with HA-CA hydrogel; MONO, injected with single hASCs in HA-CA hydrogel; and SP, injected with hASCs spheroids in HA-CA hydrogel. The rejuvenation efficacy in geriatric laryngeal muscle tissues at 12 weeks postinjection was evaluated and compared by histology, immunofluorescence staining, and functionality analysis. Total myofiber cross-sectional area and myofiber number/density, evaluated by detection of myosin heavy chain with antibodies against laminin and fast myosin heavy chain, were significantly higher in the SP group than in the other groups. The lamina propria of the larynx was evaluated by alcian blue staining, which showed that the HA was increased significantly in the SP group compared to the other groups. In functional analysis, the glottal gap area was significantly reduced in the SP group compared to the other groups. The phase difference in the vocal fold during vibration was also smaller in the SP group than in the other groups, but the difference did not reach statistical significance. Injection of hASC spheroids with hyaluronic acid-based hydrogel improves the morphological and functional characteristics of geriatric larynx.This research was supported by the Bio & Medical Technology Development Program of the National Research Foundation (NRF) funded by the Korean government (MSIT), Republic of Korea (No. 2019M3A9H1103617 and No. 2020R1A4A4079931), a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (No. HI14C1277) and the Tech-nology Innovation Program (or Industrial Strategic Technology Development Program-Bio-industrial technology development- customized diagnostic treatment products) (No. 20014955, Devel-opment of Intelligent Automation System for mass production of cell therapy products) funded By the Ministry of Trade, Industry & Energy (MOTIE), Republic of Korea

Does gender influence the impact of impaired renal function on prognosis after ST-segment elevated myocardial infarction?

Background: A limited number of studies have investigated the impact of gender on renal function and clinical outcomes after ST-segment elevated myocardial infarction (STEMI), and these studies have provided discrepant results.Methods and Results: This study was based on a retrospective cohort, the Korean Acute Myocardial Infarction Registry (KAMIR). Patients (n = 7,679) with a discharge diagnosis of STEMI were analyzed to investigate association of gender with renal function and clinical outcomes. Compared to men, women were older and exhibited more comorbidity, including impaired renal function. Women showed higher mortality compared to men (1-month mortality,5.6% in men vs. 12.6% in women, p &lt; 0.001; 1-year mortality, 6.8% in men vs. 14.4% in women, p &lt; 0.001). The risk of death proportionally increased as estimated glomerular filtration rate (eGFR) decreased in both genders. After adjusting for potential confounders, hazard ratios for women did not significantly differ from those for men at each eGFR level.The interaction test showed no significant interaction between gender and eGFR in 1-month mortality and 1-year mortality.Conclusions: Impaired renal function was an independent prognostic factor after STEMI in both genders, and the impact of impaired renal function on prognosis after STEMI did not significantly differ between genders

Efficacy of Antibiotics Sprayed into Surgical Site for Prevention of the Contamination in the Spinal Surgery

Study DesignRetrospective study.PurposeTo evaluate the effect of intraoperative wound application of vancomycin on preventing surgical wound contamination during instrumented lumbar spinal surgery.Overview of LiteraturePostoperative infection is the one of the most devastating complications of lumbar surgery. There are a few reports showing the benefits of intraoperative wound application of vancomycin during spinal surgery. However, there is no report about the effectiveness of local vancomycin instillation in prevention of surgical wound contamination.MethodsEighty-six patients underwent instrumented lumbar spinal surgery. Mean patient age was 65.19 years (range, 23-83 years). There were 67 females and 19 males. During surgery, vancomycin powder was applied into the surgical site before closure in 43 patients (antibiotic group) and vancomycin powder was not applied into the surgical site before closure in 43 patients (control group). The tip of the surgical drain was cultured to evaluate surgical wound contamination. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured on the first, third, seventh, and fourteenth day after the operation.ResultsWe found two patients with a positive culture from the tip of surgical drains in the antibiotic group, and one patient with a positive culture from the tip of the surgical drain in the control group. Postoperative ESR and CRP levels did not show significant differences between the two groups. On the third postoperative day, ESR in patients of the antibiotic group was more significantly decreased than that in patients of the control group, while CRP level did not show a significant difference between the two groups.ConclusionsThere was no evidence to suggest that intraoperative vancomycin application is effective in decreasing the risk of postoperative wound infection after instrumented posterior lumbar fusion surgery

Dichotomous role of Shp2 for naïve and primed pluripotency maintenance in embryonic stem cells

Background : The requirement of the Mek1 inhibitor (iMek1) during naïve pluripotency maintenance results from the activation of the Mek1-Erk1/2 (Mek/Erk) signaling pathway upon leukemia inhibitory factor (LIF) stimulation. Methods : Through a meta-analysis of previous genome-wide screening for negative regulators of naïve pluripotency, Ptpn11 (encoding the Shp2 protein, which serves both as a tyrosine phosphatase and putative adapter), was predicted as one of the key factors for the negative modulation of naïve pluripotency through LIF-dependent Jak/Stat3 signaling. Using an isogenic pair of naïve and primed mouse embryonic stem cells (mESCs), we demonstrated the differential role of Shp2 in naïve and primed pluripotency. Results : Loss of Shp2 increased naïve pluripotency by promoting Jak/Stat3 signaling and disturbed in vivo differentiation potential. In sharp contrast, Shp2 depletion significantly impeded the self-renewal of ESCs under primed culture conditions, which was concurrent with a reduction in Mek/Erk signaling. Similarly, upon treatment with an allosteric Shp2 inhibitor (iShp2), the cells sustained Stat3 phosphorylation and decoupled Mek/Erk signaling, thus iShp2 can replace the use of iMek1 for maintenance of naïve ESCs. Conclusions : Taken together, our findings highlight the differential roles of Shp2 in naïve and primed pluripotency and propose the usage of iShp2 instead of iMek1 for the efficient maintenance and establishment of naïve pluripotency.This work was supported by a grant from the National Research Foundation of Korea (NRF-2020R1A2C2005914). This work was also supported by the Creative-Pioneering Researchers Program through Seoul National University (SNU)

Assessment of Esophageal Reconstruction via Bioreactor Cultivation of a Synthetic Scaffold in a Canine Model

Objectives Using tissue-engineered materials for esophageal reconstruction is a technically challenging task in animals that requires bioreactor training to enhance cellular reactivity. There have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in initial epithelialization in the special environment of peristalsis. The purpose of this study was to evaluate the potential of an artificial esophagus that can enhance the regeneration of esophageal mucosa and muscle through the optimal combination of a double-layered polymeric scaffold and a custom-designed mesenchymal stem cell-based bioreactor system in a canine model. Methods We fabricated a novel double-layered scaffold as a tissue-engineered esophagus using an electrospinning technique. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. After 3 days of cultivation using the bioreactor system, tissue-engineered artificial esophagus was transplanted into a partial esophageal defect (5×3 cm-long resection) in a canine model. Results Scanning electron microscopy (SEM) showed that the electrospun fibers in a tubular scaffold were randomly and circumferentially located toward the inner and outer surfaces. Complete recovery of the esophageal mucosa was confirmed by endoscopic analysis and SEM. Esophagogastroduodenoscopy and computed tomography also showed that there were no signs of leakage or stricture and that there was a normal lumen with complete epithelialization. Significant regeneration of the mucosal layer was observed by keratin-5 immunostaining. Alpha-smooth muscle actin immunostaining showed significantly greater esophageal muscle regeneration at 12 months than at 6 months. Conclusion Custom-designed bioreactor cultured electrospun polyurethane scaffolds can be a promising approach for esophageal tissue engineering

Korean Ginseng-Induced Occupational Asthma and Determination of IgE Binding Components

A number of case reports on occupational asthma caused by herbal medicines have been issued, for example, on Sanyak, Chunkung, Banha, and Brazilian ginseng. Recently, cases of occupational asthma induced by Sanyak and Korean ginseng have been reported, but the pathogenic mechanisms involved are unknown. This study was carried out to evaluate the immunologic mechanism underlying Korean ginseng-induced occupational asthma. A patient engaged in Korean ginseng wholesale was referred for recurrent dyspnea, wheezing, and nasal symptoms, which were aggravated at work. Allergen bronchial provocation testing to Korean ginseng extract showed a typical immediate response, and skin prick testing to Korean ginseng extract also showed a strong positive response. Moreover, serum-specific IgE levels to Korean ginseng extract were significantly higher than in controls. Enzyme-linked immunosorbent assay (ELISA) inhibition tests showed a dose-dependent inhibition by Korean ginseng, but not by Dermatophagoides farinae, wheat flour, or Chinese balloon flower. Sodium dodecylsulfate-poly-acrylamide gel electrophoresis (SDS-PAGE) and immunoblotting revealed four specific Immunoglobulin E (IgE) binding components at 26, 30, 47, and 60 kDa, which were not bound by control sera. These results strongly suggest that occupation asthma induced by Korean ginseng is induced via an IgE-mediated mechanism