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1.
Otolaryngol Head Neck Surg ; 163(2): 330-334, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32423293

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has placed tremendous strain on health care systems, leading to unprecedented challenges and obstacles in the delivery of patient care. Otolaryngologists are frequently called on for inpatient consultations for an array of pathologies, ranging from chronic benign conditions to acutely life-threatening processes. Professional otolaryngologic societies across the world have proposed limiting patient care to time-sensitive and urgent matters; however, limited literature is available to describe how this transient change in philosophy may translate to clinical practice. Here we present a structured algorithm that allows for rapid triage of otolaryngologic consults during the ongoing pandemic, in efforts to minimize infectious spread and protect clinicians while preserving high-quality patient care. Considerations for managing these consults are presented, with a commentary on practical and ethical considerations.


Assuntos
Algoritmos , Betacoronavirus , Infecções por Coronavirus , Otolaringologia , Pandemias , Pneumonia Viral , Encaminhamento e Consulta , Triagem/métodos , Adulto , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Endoscopia , Humanos , Pacientes Internados , Equipamento de Proteção Individual , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , SARS-CoV-2 , Telemedicina
2.
Ann Surg Open ; 1(1): e002, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37637247

RESUMO

Introduction: Coronavirus disease 2019 (COVID-19) infections have strained hospital resources worldwide. As a result, many facilities have suspended elective operations and ambulatory procedures. As the incidence of new cases of COVID-19 decreases, hospitals will need policies and algorithms to facilitate safe and orderly return of normal activities. We describe the recommendations of a task force established in a multi-institutional healthcare system for resumption of elective operative and ambulatory procedures applicable to all hospitals and service lines. Methods: MedStar Health created a multidisciplinary task force to develop guidelines for resumption of elective surgeries/procedures. The primary focus areas included the establishment of a governance structure at each healthcare facility, prioritization of elective cases, preoperative severe acute respiratory syndrome coronavirus 2 testing, and an assessment of the needs and availability of staff, personal protective equipment, and other essential resources. Results: Each hospital president was tasked with establishing a local perioperative leadership team answering directly to them and granted the authority to prioritize elective surgery and ambulatory procedures. An elective surgery algorithm was established using a simplified Medically Necessary Time Sensitive score, with multiple steps requiring a "go/no-go" assessment based on local resources. In addition, mandatory preoperative COVID testing policies were developed and operationalized. Conclusions: Even when the COVID pandemic has passed, hospitals and surgical centers will require COVID screening and testing, case prioritization, and supply chain management to provide care essential to the surgical patient while protecting their safety and that of staff. Our guidelines consider these factors and are applicable to both tertiary academic medical centers and smaller community facilities.

3.
Otolaryngol Head Neck Surg ; 149(6): 885-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24013139

RESUMO

OBJECTIVE: To investigate surgeon preferences for perioperative management of transoral robotic surgery (TORS) and explore the frequency of postoperative complications. STUDY DESIGN: Retrospective survey. SETTING: Multi-institutional. SUBJECTS AND METHODS: An electronic survey was sent to over 300 TORS-trained surgeons in the United States identified by Intuitive Surgical, Inc. Participation was voluntary and solicited by email invitations to participate 3 times over a 1-month period. RESULTS: A total of 2015 procedures were reported by 45 respondent TORS-trained surgeons: 67% academic, 33% nonacademic. A minority of TORS procedures (n = 214, 10.6%) were performed on previously irradiated patients. Neck dissections were performed concurrently (58%) or staged (42%). Fewer than 6% of TORS procedures required tracheotomy or reconstruction. Most surgeons (62%) initiated oral intake on postoperative day 0-1. Of the patients who required readmission, bleeding (n = 62, 3.1%) was the most common cause followed by dehydration (n = 26, 1.3%). Other complications of surgery included tooth injury (n = 29, 1.4%), percutaneous endoscopic gastrostomy (PEG) dependency >6 months (n = 21, 1.0%), temporary hypoglossal nerve injury (n = 18, 0.9%), and lingual nerve injury (n = 11, 0.6%). A total of 6 deaths (0.3%) were reported within 30 days of TORS. All reported deaths were due to postoperative hemorrhage. The complication rate decreased significantly with higher surgeon case volume (>50 cases). CONCLUSIONS: TORS is associated with a low major complication rate, early initiation of oral intake, and a low rate of long-term PEG dependency. Postoperative hemorrhage was the most common cause of hospital readmission and postoperative mortality.


Assuntos
Carcinoma/cirurgia , Competência Clínica/normas , Cirurgia Endoscópica por Orifício Natural , Esvaziamento Cervical , Neoplasias Orofaríngeas/cirurgia , Robótica , Carcinoma/complicações , Desidratação/etiologia , Humanos , Cirurgia Endoscópica por Orifício Natural/métodos , Cirurgia Endoscópica por Orifício Natural/mortalidade , Duração da Cirurgia , Neoplasias Orofaríngeas/complicações , Readmissão do Paciente , Hemorragia Pós-Operatória/etiologia , Estudos Retrospectivos , Robótica/métodos , Inquéritos e Questionários , Análise de Sobrevida , Resultado do Tratamento , Estados Unidos
4.
Laryngoscope ; 123(4): 852-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23404424

RESUMO

INTRODUCTION: Transnasal endoscopy is commonly performed in an outpatient otolaryngology setting. Patients are typically administered a topical anesthetic and decongestant prior to this procedure to alleviate discomfort and improve visualization. There is no consensus on which topical anesthetic is most effective in optimizing patient experience during the procedure. OBJECTIVE: To determine whether there is a difference in the efficacy between atomized 2% tetracaine and 4% lidocaine as a topical anesthetic prior to transnasal endoscopy. STUDY DESIGN: Prospective, randomized, double-blind study. METHODS: A total of 99 patients received oxymetazoline and were randomized to receive either 2% tetracaine or 4% lidocaine prior to transnasal endoscopy. Immediately following the procedure, participants completed a survey assessing level of discomfort and other adverse symptoms pertaining to the procedure using a 10-point visual analog scale (VAS). RESULTS: There were no significant differences in VAS scores between the lidocaine and tetracaine groups. There were also no significant differences between genders in overall VAS scores and in the lidocaine and tetracaine subgroups. Older patients demonstrated significantly less discomfort or a sensation of bad taste overall. In contrast to patients receiving lidocaine, older patients receiving tetracaine experienced significantly less overall pain and discomfort, unpleasant taste, and dyspnea. CONCLUSION: In patients undergoing transnasal endoscopy, use of either 2% tetracaine or 4% lidocaine has similar effect. Tetracaine may be a better choice in older patients, however.


Assuntos
Anestésicos Locais/administração & dosagem , Endoscopia , Lidocaína/administração & dosagem , Nariz/cirurgia , Tetracaína/administração & dosagem , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
5.
Laryngoscope ; 122(3): 511-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22252670

RESUMO

OBJECTIVES/HYPOTHESIS: To determine whether the endoscopic or sublabial transseptal transsphenoidal approach for pituitary surgery has superior outcomes or decreased complication rates. STUDY DESIGN: Retrospective meta-analysis of literature. METHODS: A MEDLINE search was conducted identifying all relevant literature in the English language from 1998 through 2010. Studies explicitly identifying pure sublabial or completely endoscopic approaches were included. Meta-analysis comparing the two techniques was performed for multiple outcome measures utilizing a random effects approach. RESULTS: A total of 21 endoscopic studies (n = 2,335) and 17 sublabial studies (n = 2,565) met inclusion criteria. Analysis revealed significantly superior rates of gross tumor resection (79% vs. 65%, P < .0001), as well as lower rates of cerebral spinal fluid leak (5% vs. 7%, P < .01), septal perforation (0% vs. 5%), and postoperative epistaxis (1% vs. 4%, P < .0001) for the endoscopic approach compared to the sublabial approach. There was no difference between the two techniques in the incidence of meningitis, diabetes insipidus, or resolution of hormonal abnormality. Hospital stay (P = .01) was shorter for endoscopic surgery compared to sublabial surgery, and there was no significant difference in terms of length of operation. CONCLUSIONS: The sublabial transsphenoidal approach has been the gold standard for pituitary surgery for many years. However, meta-analysis of the recent literature demonstrates superior outcomes and decreased postoperative complications with the endoscopic approach, potentially justifying a shift toward endoscopic pituitary surgery.


Assuntos
Endoscopia/métodos , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Hipófise/cirurgia , Neoplasias Hipofisárias/cirurgia , Osso Esfenoide/cirurgia , Humanos
6.
J Clin Endocrinol Metab ; 96(9): 2684-91, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21752893

RESUMO

CONTEXT: More than 99% of thyroid cancers arise eutopically within the thyroid gland. The most frequent sites of ectopic thyroid tissue are lingual, sublingual, thyroglossal, laryngotracheal, and lateral cervical. Thyroid tissue can also be found in remote structures that were associated with the thyroid anlage during development, including the esophagus, mediastinum, heart, aorta, adrenal, pancreas, gallbladder, and skin. Ectopic thyroid tissue can be subject to the same pathological processes as normal eutopic thyroid tissue such as inflammation, hyperplasia, and tumorigenesis. The aim of this review is to describe aspects of thyroid cancer arising from the ectopic thyroid tissue in the neck in regard to epidemiology, diagnosis, and treatment and to present an illustrative series of cases of ectopic thyroid cancer. DATA ACQUISITION: We have searched the PubMed database for articles including the keywords "ectopic thyroid cancer" published between January 1, 1960, and January 1, 2011. As references, we used clinical case series, case reports, review articles, and practical guidelines focused on ectopic thyroid cancer confined to the neck region. SYNTHESIS AND CONCLUSIONS: The possibility of an ectopic thyroid cancer should be considered in the differential diagnosis of a pathological mass in the neck. Treatment of ectopic cervical thyroid cancer is based predominantly on the surgical excision of the malignant lesion. Management strategies, including performance of total thyroidectomy, neck dissection, and treatment with radioiodine, should be based on individualized risk stratification.


Assuntos
Carcinoma/patologia , Coristoma/patologia , Neoplasias de Tecidos Moles/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
7.
Ear Nose Throat J ; 89(7): E14-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20628972

RESUMO

Follicular dendritic cell sarcoma (FDCS) is a rare malignant neoplasm that can clinically mimic a number of other tumors. FDCS can follow either an indolent or aggressive course. The prognosis tends to be worse for patients with large or high-grade tumors and/or an intra-abdominal tumor site. For optimal management, complete surgical excision is recommended. Radiation therapy and/or chemotherapy may be considered for incompletely resected tumors and for tumors with poor prognostic features, but the exact role of adjuvant therapy is unknown. We report a case of cervical FDCS in a 39-year-old black man, and we review the presentation and management of this disorder, with emphasis on the differential diagnosis.


Assuntos
Sarcoma de Células Dendríticas Foliculares/diagnóstico por imagem , Sarcoma de Células Dendríticas Foliculares/cirurgia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/cirurgia , Adulto , Biópsia , Sarcoma de Células Dendríticas Foliculares/patologia , Diagnóstico Diferencial , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Masculino , Radiografia , Fatores de Risco
8.
Otolaryngol Head Neck Surg ; 137(6): 931-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18036423

RESUMO

OBJECTIVES: To understand the presentation and clinical course of angiotensin-converting enzyme (ACE) inhibitor-induced angioedema and to determine management factors associated with progression to airway compromise. STUDY DESIGN AND SETTING: Retrospective chart review of patients taking ACE inhibitors who presented to the emergency department with angioedema between December 1999 and July 2004 (n = 228). Clinical presentation, treatment, and clinical course were analyzed. RESULTS: The oral cavity was the most common location of upper-airway angioedema. Twenty-two (10%) patients required intubation, and all were intubated within 12 hours of presentation. Of the patients who required intubation, those who were started on an H(1)-blocker were extubated earlier than those not on an H(1)-blocker (P = 0.05). CONCLUSION: The locations of swelling and drooling on admission are predictive of the need for intubation. Other aspects of presentation, treatment, and disposition can help in management decisions for this potentially fatal condition. SIGNIFICANCE: This is the largest series to date of ACE inhibitor-related angioedema that challenges theories on the etiology and treatment of this condition.


Assuntos
Angioedema/induzido quimicamente , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioedema/terapia , Feminino , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Humanos , Intubação Intratraqueal , Doenças da Laringe/induzido quimicamente , Doenças da Laringe/terapia , Doenças Labiais/induzido quimicamente , Doenças Labiais/terapia , Masculino , Pessoa de Meia-Idade , Doenças da Boca/induzido quimicamente , Doenças da Boca/terapia , Soalho Bucal/efeitos dos fármacos , Palato Mole/efeitos dos fármacos , Doenças Faríngeas/induzido quimicamente , Doenças Faríngeas/terapia , Estudos Retrospectivos , Sialorreia/induzido quimicamente , Sialorreia/terapia , Doenças da Língua/induzido quimicamente , Doenças da Língua/terapia
9.
Arch Otolaryngol Head Neck Surg ; 132(1): 41-5, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16415428

RESUMO

OBJECTIVE: To identify whether perioperative 1,25-dihydroxyvitamin D or parathyroid hormone (PTH) levels will predict the development of hypocalcemia after thyroid and parathyroid surgery. DESIGN: Prospective study. SETTING: University hospital. PATIENTS: The study included 103 patients who underwent thyroid or parathyroid surgery between 2002 and 2004, with a comparison of the patients who underwent thyroid lobectomy (TL; n = 34), total thyroidectomy (TT; n = 27), parathyroid adenoma excision (PAE; n = 34), and subtotal parathyroidectomy for hyperplasia (SP; n = 8). MAIN OUTCOME MEASURES: Preoperative 1,25-dihydroxyvitamin D levels, number of patients requiring calcium replacement, and postoperative PTH and calcium levels. RESULTS: No patients in the TL or PAE group developed postoperative hypocalcemia that required calcium replacement. Six patients (22%) in the TT group and 3 patients (38%) in the SP group required calcium replacement for clinically significant hypocalcemia (P<.001). All patients who required calcium replacement had PTH levels of less than 15 pg/mL (1.6 pmol/L) 8 hours after surgery. Among the patients with postoperative PTH levels of less than 15 pg/mL (1.6 pmol/L) 8 hours after surgery, no patients in the PAE group required calcium replacement, compared with 75% of patients in the TT and SP groups (P<.001). The patients in the TT group had significantly lower postoperative calcium levels than those in the TL (P<.001) or the PAE (P<.005) group. The patients in the TL group reached stable calcium levels significantly earlier than those in the other groups (15.8 hours after surgery; P<.05). There was no relationship between preoperative 1,25-dihydroxyvitamin D levels and postoperative calcium levels. CONCLUSIONS: Preoperative 1,25-dihydroxyvitamin D levels were not predictive of postoperative calcium levels. Patients who undergo PAE or TL are at extremely low risk for requiring calcium replacement. Patients who undergo TT or SP with 8-hour postoperative PTH levels greater than or equal to 15 pg/mL (1.6 pmol/L) are at low risk for developing postoperative hypocalcemia, whereas those with PTH levels less than 15 pg/mL (1.6 pmol/L) have a high risk of developing hypocalcemia.


Assuntos
Hipocalcemia/etiologia , Doenças das Paratireoides/cirurgia , Hormônio Paratireóideo/sangue , Paratireoidectomia/efeitos adversos , Doenças da Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos , Vitamina D/análogos & derivados , Biomarcadores/sangue , Cálcio/sangue , Seguimentos , Humanos , Hipocalcemia/sangue , Doenças das Paratireoides/sangue , Período Pós-Operatório , Prognóstico , Estudos Prospectivos , Fatores de Risco , Doenças da Glândula Tireoide/sangue , Vitamina D/sangue
10.
J Am Coll Surg ; 200(5): 691-704, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15848359

RESUMO

BACKGROUND: After serial passages in monolayer, chondrocytes dedifferentiate into a fibroblast-like phenotype. Our objective was to determine if culture in alginate affects the phenotype of dedifferentiated human nasal septal chondrocytes. STUDY DESIGN: Human nasal septal chondrocytes were seeded at low density and passaged in monolayer culture. At passages (P) 1, 2, and 3 a portion of cells were cultured in alginate. Collagen, glycosaminoglycan (GAG), and DNA production were assessed. RESULTS: Chondrocytes in alginate proliferated less yet produced higher levels of GAG and collagen than those in monolayer culture. Alginate encapsulated P1 chondrocytes stained strongly for GAG and collagen type II, and minimally for collagen type I. Monolayer cells at P0 and P1 stained positively for collagen type II. All monolayer passages stained positive for collagen type I with minimal GAG staining. CONCLUSIONS: Compared with monolayer culture, alginate stimulates deposition of GAG and collagen type II, and supports the chondrocyte phenotype through P1, but does not promote redifferentiation.


Assuntos
Alginatos/farmacologia , Condrócitos/citologia , Septo Nasal/citologia , Engenharia Tecidual/métodos , Análise de Variância , Diferenciação Celular , Células Cultivadas , Condrócitos/metabolismo , Colágeno/metabolismo , DNA/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Técnicas Imunoenzimáticas , Fatores de Tempo
11.
Otol Neurotol ; 25(4): 544-52, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15241234

RESUMO

OBJECTIVE: This study compared the effectiveness of five different techniques of intratympanic gentamicin administration for Ménière's disease. DATA SOURCES: A MEDLINE search of the English language literature from 1978 to 2002 was performed using the key words "intratympanic," "gentamicin," "therapy," "Ménière's," and "disease." STUDY SELECTION: Inclusion criteria to select articles for meta-analysis were clear description of gentamicin delivery technique, clearly reported vertigo control results, and report of hearing loss posttreatment. Seven studies (n = 218) describing the multiple daily dosing technique (delivery three times per day for >or=4 d), two studies (n = 84) describing the weekly dosing technique (weekly injections for four total doses), eight studies (n = 253) of the low-dose technique (one to two injections with retreatment for recurrent vertigo), four studies (n =156) of continuous microcatheter delivery, and six studies (n =269) of the titration technique (daily or weekly doses until onset of vestibular symptoms, change in vertigo, or hearing loss) were entered into the model. DATA EXTRACTION: Vertigo control results were stratified into complete, substantial, or poor control. Hearing results were separated by profound, partial, or no hearing loss. Individuals undergoing caloric testing were separated by degree of vestibular ablation (complete versus partial) and analyzed for vertigo control (n = 301) and hearing loss (n = 333) after treatment. DATA SYNTHESIS: Comparisons between the rates of complete vertigo control, effective vertigo control (complete plus substantial control), overall hearing loss (partial plus profound), and profound hearing loss by delivery method were based on a parametric empirical Bayes analysis using binomial generalized linear models and backward variable selection (joining). Relative risk for vertigo control and hearing loss by partial or complete ablation was examined study by study using residual maximum likelihood to carry out a parametric empirical Bayes analysis. CONCLUSION: The titration method of gentamicin delivery demonstrated significantly better complete (81.7%, p = 0.001) and effective (96.3%, p < 0.05) vertigo control compared with other methods. The low-dose method of delivery demonstrated significantly worse complete vertigo control (66.7%, p < 0.001) and trends toward worse effective vertigo control (86.8%, p = 0.05) compared with other methods. The weekly method of delivery trends toward less overall hearing loss (13.1%, p = 0.08), and the multiple daily method demonstrated significantly more overall hearing loss (34.7%, p < 0.01) compared with other groups. No significant difference in profound hearing loss was found between groups. Degree of vestibular ablation after gentamicin therapy is not significantly correlated with the resulting vertigo control or hearing loss status.


Assuntos
Antibacterianos/uso terapêutico , Gentamicinas/uso terapêutico , Doença de Meniere/tratamento farmacológico , Antibacterianos/administração & dosagem , Ablação por Cateter , Gentamicinas/administração & dosagem , Perda Auditiva , Humanos , Doença de Meniere/complicações , Resultado do Tratamento , Vertigem , Vestíbulo do Labirinto/cirurgia
12.
Laryngoscope ; 114(1): 38-45, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14709992

RESUMO

OBJECTIVES: Tissue engineering of nasal septal cartilage has numerous potential applications in craniofacial reconstruction. Chondrocytes suspended in alginate gel have been shown to produce a substantial cell-associated matrix. The objective of this study was to determine whether cartilage tissue could be generated using the alginate-recovered-chondrocyte (ARC) method, in which chondrocytes are cultured in alginate as an intermediate step in tissue fabrication. METHODS: Nasal septal chondrocytes from five patient donors were isolated by enzymatic digestion, then expanded in monolayer culture. At confluency, a portion of those cells were seeded at high density onto a semipermeable membrane and cultured for 14, 21, or 28 days (monolayer group). The remaining cells were suspended in alginate and cultured until a cell-associated matrix was observed (10-17 days). Cells and their associated matrix were released from alginate (ARC group), seeded onto a semipermeable membrane, and cultured as already described. DNA (Hoechst 33258 Assay), glycosaminoglycan (GAG; dimethylmethylene blue assay), and collagen (hydroxyproline assay) were analyzed biochemically. Immunohistochemistry was performed to assess expression of collagens type I and type II. Histochemistry was performed to localize cells accumulating sulfated GAG (Alcian blue stain). RESULTS: The ARC constructs, in contrast to the monolayer constructs, had substantial structural stability and the histologic and gross appearance of cartilaginous tissue. ARC constructs demonstrated significantly greater GAG and collagen accumulation than monolayer constructs (P <.05). Histologic analysis revealed substantial GAG and collagen type II production and only moderate collagen type I production. The composition of the matrix was thus similar to that of native human septal cartilage. CONCLUSIONS: Tissue-engineered human nasal septal cartilage using the ARC method has the histologic and gross appearance of native cartilage and has biochemical composition more like that of native cartilage than monolayer constructs. This is the first report of human nasal septal neocartilage formation without the use of biodegradable scaffolds.


Assuntos
Condrócitos/citologia , Septo Nasal/citologia , Engenharia Tecidual/métodos , Alginatos , Células Cultivadas , Colágeno/metabolismo , DNA/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Imuno-Histoquímica , Fatores de Tempo
13.
Laryngoscope ; 113(1): 25-32, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12514377

RESUMO

OBJECTIVES/HYPOTHESIS: Tissue engineering laboratories are attempting to create neocartilage that could serve as an implant material for structural support during reconstructive surgery. One approach to forming such tissue is to proliferate chondrocytes in monolayer culture and then seed the expanded cell population onto biodegradable scaffolds. However, chondrocytes are known to dedifferentiate after this type of monolayer growth and, as a result, decrease their production of cartilaginous extracellular matrix components such as sulfated glycosaminoglycans. The resultant tissue lacks the biomechanical properties characteristic of cartilage. The objective of the study was to determine whether different culture systems could induce monolayer-expanded human septal chondrocytes to redifferentiate and form extracellular matrix. STUDY DESIGN: Laboratory research. METHODS: Chondrocytes were isolated from human nasal septal cartilage of five donor patients (age, 35.8 +/- 9.3 y). Cell populations were seeded at low density (30,000 cells/cm2) into monolayer culture and expanded for 4 to 6 days. Following trypsin release, chondrocytes were placed into three different systems for neocartilage formation: alginate beads, polyglycolic acid scaffolds, and monolayer. After 7 and 14 days of growth, neocartilage was analyzed using histological and quantitative biochemical assessment of cellularity (Hoechst 33258 assay) and sulfated glycosaminoglycan content (dimethyl methylene blue assay). RESULTS: Histologically, alginate beads contained spherical chondrocytes surrounded by dense extracellular matrix, an appearance similar to that of native cartilage. In contrast, polyglycolic acid scaffolds and monolayer cultures contained elongated cells with scant staining for matrix sulfated glycosaminoglycans, which are features that are characteristic of dedifferentiated chondrocytes. Biochemical analysis demonstrated a lower level of cell proliferation (P <.001) in scaffolds (+52% over baseline) and alginate (+96% over baseline) than in monolayer (+366% over baseline), as well as a higher content of sulfated glycosaminoglycans per cell (P <.001), after 14 days of growth in alginate culture than in either polyglycolic acid scaffolds (19-fold difference) or monolayer (98-fold difference). CONCLUSIONS: Of the systems compared, monolayer-expanded human septal chondrocytes demonstrated the greatest accumulation of sulfated glycosaminoglycans per cell when grown in alginate beads. Future research on cartilage tissue engineering may use alginate culture for reverting dedifferentiated cells back to the chondrocytic phenotype.


Assuntos
Alginatos/farmacologia , Cartilagem/metabolismo , Condrócitos/efeitos dos fármacos , Ácido Poliglicólico/farmacologia , Engenharia Tecidual/métodos , Alginatos/metabolismo , Cartilagem/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Células Cultivadas , Condrócitos/fisiologia , Meios de Cultivo Condicionados , Humanos , Septo Nasal , Ácido Poliglicólico/metabolismo , Sensibilidade e Especificidade , Transplante de Tecidos/métodos , Coleta de Tecidos e Órgãos/métodos
14.
Int J Pediatr Otorhinolaryngol ; 62(3): 249-52, 2002 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-11852129

RESUMO

Choanal atresia is postulated to be secondary to an abnormality of the rupture of the buccopharyngeal membrane during the embryological period. This condition usually occurs sporadically, but has been described in siblings and successive generations. The genetics remain unclear. We present monozygotic twins with identical findings of unilateral choanal atresia and no other associated anomalies. To our knowledge, this is the first report of such an occurrence.


Assuntos
Atresia das Cóanas , Doenças em Gêmeos , Gêmeos Monozigóticos , Alquilantes/uso terapêutico , Criança , Atresia das Cóanas/diagnóstico , Atresia das Cóanas/genética , Atresia das Cóanas/cirurgia , Endoscopia , Humanos , Masculino , Mitomicina/uso terapêutico , Procedimentos Cirúrgicos Otorrinolaringológicos , Tomografia Computadorizada por Raios X
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