33 results on '"Gordon CB"'
Search Results
2. Does crown, root, and bone visualization in a clear aligner virtual setup impact treatment decisions?
- Author
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Tüfekçi E, Carrico CK, Gordon CB, and Lindauer SJ
- Subjects
- Humans, Patient Care Planning, Tooth Crown diagnostic imaging, Surveys and Questionnaires, Clinical Decision-Making, Adult, Treatment Outcome, Tooth Root diagnostic imaging, Imaging, Three-Dimensional methods
- Abstract
Introduction: Clear aligner technology based on a machine learning algorithm is currently available for orthodontic treatment. Treatment planning on the basis of 3-dimensional crown, root, and bone imaging is claimed to provide accurate diagnosis and better treatment outcomes for adult patients with complex needs. This study aimed to answer the following questions: (1) would practitioners modify their original treatment plan once provided with the crown, root, and bone view? and (2) does practitioner satisfaction regarding treatment outcomes change once the crown, root, and bone view is provided?, Methods: An online questionnaire was emailed to members of the American Association of Orthodontists (n = 2300) and the Virginia Orthodontic Education and Research Foundation (n = 211). The survey consisted of videos of 4 patients shown in 2 presentations: crown-only and crown, root, and bone views, generated by artificial intelligence-driven treatment planning software (3D Predict aligner system; 3D Predict, New York, NY). Respondents were asked to answer treatment-related questions and rate the treatment outcomes using a visual analog scale. Statistical analyses were completed to determine the significance of crown, root, and bone view on treatment planning with clear aligners., Results: A total of 70 orthodontists participated in the survey. There were significant differences in responses when viewing patients in crown-only and crown, root, and bone presentations. Across the 4 patients, 33%-43% of practitioners changed their sentiment toward the treatment plan (P <0.001). When rating satisfaction on the 100-point scale, average ratings changed by 10.6 to 21.0 points; both increases and decreases in satisfaction were seen across the patients (P <0.001)., Conclusions: When given 3-dimensional information on the position of a patient's crowns, root, and bone coverage, orthodontists are likely to change their clear aligner treatment plan. This study showed that a confirmation of dehiscence and fenestrations using the root and bone view resulted in practitioner dissatisfaction despite an initial satisfaction with the crown-only view., (Copyright © 2024 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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3. Transfacial Two-pin External Mandibular Distraction Osteogenesis: A Technique for Neonatal Airway Obstruction from Robin Sequence.
- Author
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Babiker HE, Runyan CM, Bins GP, Oliver JD, Massary DA, Lor LS, Rapp SJ, Pan BS, and Gordon CB
- Abstract
Surgical management in those with moderate-to-severe airway obstruction includes tongue-lip adhesion, tracheostomy, and/or mandibular distraction osteogenesis. This article describes a transfacial two-pin external device technique for mandibular distraction osteogenesis, utilizing minimal dissection., Methods: The first percutaneous pin is transcutaneously placed just inferior to the sigmoid notch parallel to the interpupillary line. The pin is then advanced through the pterygoid musculature at the base of the pterygoid plates, toward the contralateral ramus, and exits the skin. A second parallel pin is placed spanning the bilateral mandibular parasymphysis distal to the region of the future canine. With the pins in place, bilateral high ramus transverse corticotomies are performed. Using univector distractor devices, the length of activation varies, with the goal of overdistraction to achieve a class III relationship of the alveolar ridges. Consolidation is limited to a 1:1 period with the activation phase, and removal is performed by cutting and pulling the pins out of the face., Results: To guide optimal transcutaneous pin placement, transfacial pins were then placed through twenty segmented mandibles. Mean upper pin (UP) distance was 20.7 ± 1.1 mm from the tragus. The distance between the cutaneous entry of the UP and lower pin was 23.5 ± 0.9 mm, and the tragion-UP-lower pin angle was 118.7 ± 2.9°., Conclusions: The two-pin technique has potential advantages regarding nerve injury and mandibular growth, given an intraoral approach with limited dissection. It may safely be performed on neonates whose small size may preclude the use of internal distractor devices., Competing Interests: The authors have no financial interest to declare in relation to the content of this article. Disclosure statements are at the end of this article, following the correspondence information., (Copyright © 2023 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons.)
- Published
- 2023
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4. Digital-Facial Translocation in Amniotic Band Sequence: Evidence of the Intrinsic Theory.
- Author
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Weinstein B, Hassouba M, Flores RL, Staffenberg DA, Gordon CB, and Runyan CM
- Subjects
- Facial Bones abnormalities, Female, Humans, Infant, Newborn, Male, Abnormalities, Multiple diagnosis, Amniotic Band Syndrome diagnosis, Face abnormalities, Hand Deformities, Congenital diagnosis, Hypertelorism diagnosis
- Abstract
Amniotic band sequence is a complex congenital anomaly in which infants with typically no known genetic mutation have bands of maternal amniotic tissue wrapped around body parts, most commonly the limbs and digits. The authors report a novel variation on this presentation in 3 patients from 2 centers with complex craniofacial clefting and amniotic band sequence. They presented with hypertelorism, different forms of complex craniofacial clefting, and bands connecting ipsilateral hands to facial clefts, with digital-facial translocation in 2 cases. These findings support a model in which complex craniofacial clefts result in areas of exposed, sticky, and temporally and spatially coincident mesenchyme within the embryo that are susceptible to adherence of ipsilateral fetal hands. This strongly supports the intrinsic and adhesion theories of the etiology of amniotic band syndrome.
- Published
- 2018
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5. Management of Airway Obstruction in Infants With Pierre Robin Sequence.
- Author
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Runyan CM, Uribe-Rivera A, Tork S, Shikary TA, Ehsan Z, Weaver KN, Hossain MM, Gordon CB, and Pan BS
- Abstract
Background: Pierre Robin sequence (PRS)-related airway obstruction is often treated surgically; however, objective measures predicting the need for surgery are poorly defined., Methods: A retrospective chart review was performed on 171 neonates with PRS. Infants were grouped based upon intervention modality: nonsurgical (conservative) or surgical [mandibular distraction osteogenesis (MDO) or tracheostomy]. Demographic data, physical examination findings, and study results were compared between groups to determine risk factors for surgical intervention, and to predict long-term success or failure of those interventions., Results: The most significant, objective risk factor among those receiving surgery was a poor preintervention sleep study [obstructive index (OI): 42.4 versus 12.9 for the conservative treatment group; P < 0.001]. Only 11% of those treated conservatively had an OI >20, whereas 67.5% of those treated surgically met this severity measure. Of those receiving surgery, tracheostomy was associated with neurologic impairment ( P = 0.030) and low birth weight ( P = 0.046) compared with the MDO group. Together with syndromic status, these risk factors were useful for predicting failure of MDO to avoid subsequent tracheostomy (test sensitivity and specificity were 64.2% and 100.0%, respectively). No long-term differences in speech or micrognathia were detected between the 3 groups; however, those treated conservatively or with MDO had improved long-term feeding and airway obstruction outcomes compared with the tracheostomy group., Conclusions: Surgical intervention for PRS-related tongue-based airway obstruction should be strongly considered with an OI >20. Tracheostomy should be reserved for complex patients with concomitant syndromic diagnosis, neurologic impairment, and low birth weight.
- Published
- 2018
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6. Decannulation and Airway Outcomes With Maxillomandibular Distraction in Treacher Collins and Nager Syndrome.
- Author
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Biskup NI, Pan BS, Elhadi-Babiker H, Hathaway RR, van Aalst J, and Gordon CB
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Facial Bones surgery, Female, Humans, Male, Retrospective Studies, Young Adult, Airway Extubation statistics & numerical data, Mandibulofacial Dysostosis surgery, Orthognathic Surgical Procedures, Osteogenesis, Distraction, Tracheostomy statistics & numerical data
- Abstract
Background: Treacher Collins syndrome is a rare disorder (1/50,000 live births) with features that include hypoplastic orbitozygomatic complex with downward slanting eyes, and maxillary/mandibular retrusion. Obstructive sleep apnea and tracheostomy-dependence are common. This study presents the outcomes of skeletal distraction on avoidance of tracheostomy and decannulation in this patient population., Methods: The authors reviewed charts of all patients with Treacher Collins syndrome who underwent craniofacial reconstruction from 2003 to 2016. Primary outcome measures included decannulation of tracheostomy dependent patients and avoidance of tracheostomy. Secondary outcome measures included cephalometric parameters, polysomnography scores, and airway exposure scores on direct laryngoscopy., Results: Twenty-five patients underwent mandibular and maxillary advancement to resolve upper airway obstruction. Mandibular distraction was performed in 24 of 25 patients, and maxillary distraction in 14 of 25 patients. Maxillary distraction was combined with mandibular distraction in 13 of 17 to accomplish greater advancement and counter-clockwise rotation of the entire maxillary-mandibular complex. Six of 7 patients, 85.7%, avoided a tracheostomy and 39% (7 of 18) were decannulated. Cephalometric changes in sella-nasion-A point, sella-nasion-B , occlusal plane angle, and posterior airway space were equivalent between the groups who were able to clear their obstruction and those who were not., Conclusions: Treacher Collins is a very challenging disease in which to resolve airway obstruction. Thus, thorough evaluation of the entire airway for all levels of obstruction is critical to successful outcomes. Future collaborative efforts between multiple institutions can help to increase our understanding and effective management of this rare disease.
- Published
- 2018
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7. Neonatal Mandibular Distraction Without a Consolidation Period: Is It Safe? Is it Effective?
- Author
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Biskup N, Altman AL, Runyan CM, Gendron C, Babiker HE, Gordon CB, and Pan BS
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- Bone Remodeling, Female, Humans, Infant, Newborn, Male, Osteogenesis, Distraction methods, Outcome and Process Assessment, Health Care, Polysomnography methods, Postoperative Period, Retrospective Studies, Treatment Outcome, Airway Obstruction diagnosis, Airway Obstruction etiology, Mandible diagnostic imaging, Mandible pathology, Mandible surgery, Mandibular Reconstruction adverse effects, Mandibular Reconstruction methods, Pierre Robin Syndrome surgery, Postoperative Complications diagnosis, Postoperative Complications prevention & control
- Abstract
Purpose: Consolidation is a standard part of most post-distraction protocols. This study aims to determine whether the deliberate omission of a consolidation period following mandibular distraction (MD) in neonates with Pierre Robin sequence (PRS) affected the airway outcomes and complication rates., Patients and Methods: A retrospective chart review of 28 neonates with PRS who underwent MD for severe airway obstruction between 2009 and 2014 was performed. Neonates were split into 2 cohorts: those with a very short or no consolidation (no consolidation group, n = 18) and those with a traditional consolidation period (consolidation group, n = 10)., Results: Mean consolidation length was 25 days in the conventional consolidation group and 1.5 days in the no consolidation group (P < 0.01). Postoperatively, both groups showed equivalent improvements in their obstructive index as measured by polysomnography. Compared with the patients who underwent convention consolidation, patients in the "no consolidation" group did not require a greater number of repeat distraction, supplemental oxygen, or tracheostomy. Nor was there any significant difference in the number of complications between the 2 groups., Conclusion: In neonates with PRS treated with MD for severe airway obstruction, the omission of a consolidation period does not appear to significantly affect the complication rate or resolution of airway obstruction.
- Published
- 2017
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8. Enzyme replacement therapy for congenital hypophosphatasia allows for surgical treatment of related complex craniosynostosis: a case series.
- Author
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Kosnik-Infinger L, Gendron C, Gordon CB, Pan BS, van Aalst JA, and Vogel TW
- Subjects
- Child, Preschool, Craniosynostoses diagnosis, Female, Humans, Hypophosphatasia diagnosis, Male, Postoperative Care methods, Treatment Outcome, Alkaline Phosphatase administration & dosage, Craniosynostoses drug therapy, Craniosynostoses surgery, Enzyme Replacement Therapy methods, Hypophosphatasia drug therapy, Hypophosphatasia surgery, Immunoglobulin G administration & dosage, Recombinant Fusion Proteins administration & dosage
- Abstract
Hypophosphatasia (HPP) is a rare inherited disorder of bone metabolism that results in the loss of function of the gene coding for tissue-nonspecific alkaline phosphatase (TNSALP). Patients with HPP have defective bone mineralization as well as craniosynostosis that can be seen in the infantile and childhood forms of this disease. Traditionally, HPP has had a poor prognosis, with few children surviving to exhibit the phenotype of clinical craniosynostosis that requires surgical intervention. Here, the authors report on new advancements in enzyme replacement therapy (ERT) for children affected by HPP, allowing these patients to survive and undergo surgery to address complex craniosynostosis. The authors discuss their case series of 4 HPP patients treated at their institution with ERT who have undergone successful surgical intervention for craniosynostosis. These children had no complications related to their surgeries and exhibited decreased neurological symptoms following cranial vault remodeling. This study reveals that ERT administered either pre- or post- operatively paired with cranial vault remodeling strategies can yield improved neurological outcomes in children affected by HPP.
- Published
- 2015
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9. Pediatric frontal sinus fractures: outcomes and treatment algorithm.
- Author
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Vu AT, Patel PA, Chen W, Wilkening MW, and Gordon CB
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- Adolescent, Adult, Child, Child, Preschool, Cohort Studies, Female, Follow-Up Studies, Humans, Male, Postoperative Complications etiology, Retrospective Studies, Skull Fractures diagnosis, Algorithms, Frontal Sinus injuries, Frontal Sinus surgery, Skull Fractures surgery
- Abstract
Pediatric frontal sinus fractures are a rare clinical entity. Owing to the large amount of force required to fracture the frontal sinus, it is often associated with severe intracranial and craniofacial injuries. The treatment of frontal sinus fractures is controversial, with many different established algorithms based mainly on the adult population. The authors present their experience with pediatric frontal sinus fractures; they also present a treatment algorithm. A retrospective review of the Cincinnati Children's Hospital Medical Center trauma database was performed. From 1998 to 2010, the authors identified patients between the ages of 0 and 18 with frontal sinus fractures and analyzed demographics, fracture pattern, associated injuries, methods of treatment, and complications. Descriptive statistics and univariate analyses were performed.A total of 39 patients were included in the study with a mean follow-up of 31.2 months. Fractures of the anterior and posterior table with displacement greater than one table width were significantly associated with higher hospital costs, higher velocity mechanism of injuries, lower Glasgow Coma Scale scores, nasofrontal outflow tract (NFOT) involvement, and cerebrospinal fluid leak. There were no differences in short- and long-term complications. Additionally, these patients were more likely to be treated surgically in the form of obliteration or cranialization.Patients without NFOT involvement can be managed with observation only. Patients with NFOT involvement or persistent cerebrospinal fluid leak should be treated with obliteration or cranialization, respectively, to reduce the risk of severe complications.
- Published
- 2015
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10. Cost analysis of mandibular distraction versus tracheostomy in neonates with Pierre Robin sequence.
- Author
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Runyan CM, Uribe-Rivera A, Karlea A, Meinzen-Derr J, Rothchild D, Saal H, Hopkin RJ, and Gordon CB
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- Cohort Studies, Costs and Cost Analysis, Female, Humans, Infant, Infant, Newborn, Length of Stay, Male, Retrospective Studies, Mandible abnormalities, Mandible surgery, Osteogenesis, Distraction economics, Pierre Robin Syndrome economics, Pierre Robin Syndrome surgery, Tracheostomy economics
- Abstract
Objective: To evaluate costs associated with surgical treatment for neonates with Pierre Robin sequence (PRS)., Study Design: Retrospective cohort study., Setting: Cincinnati Children's Hospital Medical Center., Subjects and Methods: With Institutional Review Board approval, we retrospectively studied neonates with PRS treated from 2001 to 2009 with either tracheostomy (Trach), mandibular distraction (MD), or Trach with subsequent MD (Trach+MD). Actual charges over a 3-year period associated with operative costs, hospital stay, imaging and sleep studies, clinic visits, and related emergency room visits were collected. Home tracheostomy care charges were estimated individually for each patient. Charges were compared using regression and appropriate statistical analyses., Results: Forty-seven neonates were included in the study (MD, n = 26; Trach, n = 12; Trach+MD, n = 9). Trach group patients had 2.6-fold higher charges than the MD group despite no difference in length of hospital stay. This difference increased to 7.3-fold when including home trach care-related costs. Trach+MD group patients had longer hospital lengths of stay and higher operation room (OR) fees, but no increased total charges compared with the Trach only group., Conclusions: For patients with severe PRS, mandibular distraction provides significant cost savings over tracheostomy ($300,000 per patient over 3 years). Increased costs with tracheostomy come from greater hospital-related charges, more frequent airway procedures, a higher incidence of gastrostomy tube feeds, and home trach care costs. A careful examination of long-term outcomes will be critical as mandibular distraction continues to gain acceptance for treatment of PRS., (© American Academy of Otolaryngology-Head and Neck Surgery Foundation 2014.)
- Published
- 2014
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11. Evolution in minimal-incision palatoplasty: surgical technique and outcomes in 67 consecutive cases.
- Author
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Pan BS, Rapp SJ, Vu A, Uribe-Rivera A, Billmire DA, and Gordon CB
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- Female, Humans, Infant, Male, Minimally Invasive Surgical Procedures, Plastic Surgery Procedures trends, Retrospective Studies, Treatment Outcome, Cleft Palate surgery, Plastic Surgery Procedures methods
- Abstract
Background: Conventional palatoplasty relies on extensive mucosal incisions and isolation of flaps on the palatine vessels to facilitate midline closure and velar reconstruction. This introduces substantial scarring, which has adverse effects on vascularity and growth. The authors have developed a minimally invasive palatoplasty technique that may have advantages over traditional techniques. The authors present their operative experience and outcomes when using the minimally invasive method paired with a novel cranial base maneuver for nasal mucosa closure., Methods: Based on cadaveric dissections, the authors developed a modified minimal-incision approach that permits anatomical reconstruction from a midline approach. From 2003 to 2010, a retrospective review was performed on 67 consecutive minimal-incision palatoplasties. Cases requiring relaxing incision and/or conversion to other palatoplasty techniques were compared with minimal incision alone., Results: Minimally invasive palatoplasty alone was able to be performed in 78 percent (n=52) of all cases. Fistula rates were 7.6 percent (n=4) in the minimally invasive palatoplasty group and 20 percent (n=3) in the relaxing/conversion group (p=0.04). Of patients requiring relaxing incisions/conversion, a higher percentage were syndromic (73 percent; p=0.01). Eighty-nine percent of all Veau class I defects were able to be successfully closed with the minimally invasive palatoplasty approach (p=0.01)., Conclusions: Minimal-incision palatoplasty paired with a cranial base maneuver for nasal mucosa elevation results in adequate soft-tissue mobility and length to arrive at a tension-free closure. Fistula and velopharyngeal insufficiency rates are comparable to that of other techniques, and theoretical advantages of this technique will be borne out by longer term follow-up., Clinical Question/level of Evidence: Therapeutic, III.
- Published
- 2014
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12. Outcomes of mandibular distraction osteogenesis in the treatment of severe micrognathia.
- Author
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Lam DJ, Tabangin ME, Shikary TA, Uribe-Rivera A, Meinzen-Derr JK, de Alarcon A, Billmire DA, and Gordon CB
- Subjects
- Adolescent, Airway Obstruction etiology, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Micrognathism complications, Ohio, Pierre Robin Syndrome complications, Postoperative Complications, Retrospective Studies, Time Factors, Treatment Outcome, Young Adult, Airway Obstruction surgery, Micrognathism surgery, Osteogenesis, Distraction methods, Pierre Robin Syndrome surgery
- Abstract
Importance: Patients with severe micrognathia are predisposed to airway obstruction. Mandibular distraction osteogenesis (MDO) is an alternative to tracheotomy that lengthens the mandible in order to improve the retrolingual airway. This study presents outcomes from one of the largest cohorts reported., Objective: To assess the rate and predictors of surgical success and complications among (1) patients who underwent MDO prior to other airway procedures (MDO first), and (2) patients who required an initial tracheotomy and were subsequently treated with MDO (tracheotomy first)., Design, Setting, and Participants: Retrospective cohort study at a tertiary care pediatric medical center of patients diagnosed as having micrognathia resulting in symptomatic airway obstruction (Pierre Robin sequence) and who underwent MDO from September 1995 to December 2009., Interventions: Electronic medical records were reviewed. Multivariable regression analysis was used to assess for predictors of outcome., Main Outcomes and Measures: Rates of surgical success (defined as either tracheotomy avoidance or decannulation) and complications. Potential predictors included demographics, syndrome presence, follow-up time, and surgical history., Results: A total of 123 patients (61 in MDO-first subgroup, 62 in tracheotomy-first subgroup) underwent MDO during the study period. Median age at time of distraction was 21 months (range, 7 days-24 years). Surgical success and complication rates were 83.6% and 14.8% in the MDO-first subgroup and 67.7% and 38.7% in the tracheotomy-first subgroup. Tracheotomy-first patients were more likely to have a syndromic diagnosis (66.0% vs 43.0%; P = .009) and were older at the time of MDO (median age, 30 months vs 5.1 months; P < .001). Poorer odds of success were associated with the need for 2 or more other airway procedures (odds ratio [OR], 0.14 [95% CI, 0.02-0.82]) in the MDO-first subgroup and craniofacial microsomia or Goldenhar syndrome (OR, 0.07 [95% CI, 0.009-0.52]) in the tracheotomy-first subgroup., Conclusions and Relevance: Mandibular distraction osteogenesis has a high rate of success in avoiding tracheotomy. Patients who required a tracheotomy before MDO had a lower success rate in achieving decannulation and a higher rate of complications. However, these patients also had a higher rate of syndromic diagnoses and associated comorbidities. Patients with Goldenhar syndrome have a decreased likelihood of surgical success.
- Published
- 2014
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13. TGFβ signaling regulates lipogenesis in human sebaceous glands cells.
- Author
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McNairn AJ, Doucet Y, Demaude J, Brusadelli M, Gordon CB, Uribe-Rivera A, Lambert PF, Bouez C, Breton L, and Guasch G
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- Breast cytology, Cell Differentiation, Cells, Cultured, Child, Child, Preschool, Face, Fibronectins metabolism, Humans, Infant, Scalp cytology, Signal Transduction, Thorax cytology, Cell Culture Techniques methods, Lipogenesis physiology, Sebaceous Glands cytology, Sebaceous Glands metabolism, Transforming Growth Factor beta metabolism
- Abstract
Background: Sebaceous glands are components of the skin essential for its normal lubrication by the production of sebum. This contributes to skin health and more importantly is crucial for the skin barrier function. A mechanistic understanding of sebaceous gland cells growth and differentiation has lagged behind that for keratinocytes, partly because of a lack of an in vitro model that can be used for experimental manipulation., Methods: We have developed an in vitro culture model to isolate and grow primary human sebocytes without transformation that display functional characteristics of sebocytes. We used this novel method to probe the effect of Transforming Growth Factor β (TGFβ) signaling on sebocyte differentiation, by examining the expression of genes involved in lipogenesis upon treatment with TGFβ1. We also repressed TGFβ signaling through knockdown of the TGFβ Receptor II to address if the effect of TGFβ activation is mediated via canonical Smad signal transduction., Results: We find that activation of the TGFβ signaling pathway is necessary and sufficient for maintaining sebocytes in an undifferentiated state. The presence of TGFβ ligand triggered decreased expression in genes required for the production of characteristics sebaceous lipids and for sebocyte differentiation such as FADS2 and PPARγ, thereby decreasing lipid accumulation through the TGFβ RII-Smad2 dependent pathway., Conclusion: TGFβ signaling plays an essential role in sebaceous gland regulation by maintaining sebocytes in an undifferentiated state. This data was generated using a novel method for human sebocyte culture, which is likely to prove generally useful in investigations of sebaceous gland growth and differentiation. These findings open a new paradigm in human skin biology with important implications for skin therapies.
- Published
- 2013
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14. Extended composite temporoparietal fascial flap: clinical implications for tissue engineering in mandibular reconstruction.
- Author
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Patel PA, Chen W, Wilkening MW, Uribe-Rivera A, Racadio JM, and Gordon CB
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- Cadaver, Humans, Periosteum surgery, Fasciotomy, Mandibular Reconstruction methods, Surgical Flaps blood supply, Temporal Arteries surgery, Tissue Engineering
- Abstract
Background: The authors have expanded upon a well-described and widely used flap in the head and neck region. The purpose of the cadaver study was to determine the feasibility, angiosome, and the potential application of this pedicled flap in bone tissue engineering of the mandible., Methods: A total of 6 fresh human cadaver heads were dissected for a total of 12 flaps. The extended composite temporoparietal fascial flap, based on the superficial temporal artery (STA) and including cranial periosteum, was dissected and the dimensions were measured. Through a combined submandibular and preauricular incision, the mandible was exposed and the dimensions were measured from the sigmoid notch to the gonion angle and from the gonion angle to the symphysis. CT angiography and silicone injections were performed to identify the vascular anatomy of the flap., Results: The combined distance from the sigmoid notch to the gonion and the gonion to the symphysis, plotted versus the cranial apex to tragus length, demonstrated adequate flap dimensions in all specimens for hemi-mandibular reconstruction. The average flap length was 16.5 ± 1.40 cm and the average flap width was 11.4 ± 0.98 cm, resulting in an average flap surface area of 94.5 ± 13.08 cm. Radiographic images and silicone injections confirmed STA perfusion of the cranial periosteum., Conclusions: The extended composite temporoparietal fascial flap with periosteum can be a viable option for providing vascularized periosteum in tissue-engineered craniofacial reconstruction.
- Published
- 2013
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15. External fixation in a low-velocity gunshot wound to the mandible.
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Wilkening MW, Patel PA, and Gordon CB
- Subjects
- Adult, Humans, Internal Fixators, Male, Jaw Fixation Techniques, Mandibular Injuries surgery, Wounds, Gunshot surgery
- Abstract
Low-velocity gunshot wounds to the mandible are complex injuries that can be aesthetically and functionally devastating. Despite advances in plating systems and surgical techniques, repair of such injuries remains a challenging endeavor. Traditionally, external fixation has resulted in longer treatment times and the need for revision surgery. Rigid fixation has many proponents because of shorter postoperative treatment times and fewer complications. We report a case of a low-velocity gunshot injury to the mandible with comminution and a full-thickness soft tissue wound treated definitively with maxillomandibular fixation and an external fixation device.
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- 2012
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16. A Drosophila model of the neurodegenerative disease SCA17 reveals a role of RBP-J/Su(H) in modulating the pathological outcome.
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Ren J, Jegga AG, Zhang M, Deng J, Liu J, Gordon CB, Aronow BJ, Lu LJ, Zhang B, and Ma J
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- Animals, Animals, Genetically Modified, Blotting, Western, Drosophila, Drosophila Proteins genetics, Humans, Immunoprecipitation, Microarray Analysis, Neurodegenerative Diseases genetics, Repressor Proteins genetics, Spinocerebellar Ataxias genetics, TATA-Box Binding Protein genetics, Drosophila Proteins metabolism, Neurodegenerative Diseases metabolism, Repressor Proteins metabolism, Spinocerebellar Ataxias metabolism, TATA-Box Binding Protein metabolism
- Abstract
Expanded polyglutamine (polyQ) tract in the human TATA-box-binding protein (hTBP) causes the neurodegenerative disease spinocerebellar ataxia 17 (SCA17). To investigate the pathological effects of polyQ expansion, we established a SCA17 model in Drosophila. Similar to SCA17 patients, transgenic flies expressing a mutant hTBP protein with an expanded polyQ tract (hTBP80Q) exhibit progressive neurodegeneration, late-onset locomotor impairment and shortened lifespan. Microarray analysis reveals that hTBP80Q causes widespread and time-dependent transcriptional dysregulation in Drosophila. In a candidate screen for genetic modifiers, we identified RBP-J/Su(H), a transcription factor that contains Q/N-rich domains and participates in Notch signaling. Knockdown of Su(H) by RNAi further enhances hTBP80Q-induced eye defects, whereas overexpression of Su(H) suppresses such defects. While the Su(H) transcript level is not significantly altered in hTBP80Q-expressing flies, genes that contain Su(H)-binding sites are among those that are dysregulated. We further show that hTBP80Q interacts more efficiently with Su(H) than wild-type hTBP, suggesting that a reduction in the fraction of Su(H) available for its normal cellular functions contributes to hTBP80Q-induced phenotypes. While the Notch signaling pathway has been implicated in several neurological disorders, our study suggests a possibility that the activity of its nuclear component RBP-J/Su(H) may modulate the pathological progression in SCA17 patients.
- Published
- 2011
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17. Endoscopic monobloc advancement with ultrasonic osteotomy: a feasibility study.
- Author
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Maercks RA, Taylor JA, and Gordon CB
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- Adult, Cadaver, Craniotomy instrumentation, Craniotomy methods, Dissection methods, Dura Mater anatomy & histology, Dura Mater surgery, Feasibility Studies, Frontal Bone surgery, Humans, Maxilla surgery, Orbit surgery, Osteotomy instrumentation, Periosteum anatomy & histology, Risk Factors, Sphenoid Bone surgery, Temporal Bone surgery, Time Factors, Treatment Outcome, Ultrasonic Therapy instrumentation, Endoscopy methods, Facial Bones surgery, Osteogenesis, Distraction methods, Osteotomy methods, Ultrasonic Therapy methods
- Abstract
Background: The monobloc procedure has been criticized owing to its tendency for cerebrospinal fluid leak, relapse, infection, and incomplete ossification. Such risks have been decreased through gradual advancement of the monobloc via distraction osteogenesis. This cadaver study was undertaken to develop an endoscopic, ultrasonic monobloc osteotomy to further minimize risks and potentially improve outcomes., Methods: Three fresh, adult human cadavers were used in this study. Endoscopic ultrasonic monobloc osteotomy was completed in all cadavers with 3 incisions hidden in the hair-bearing scalp. The incisions afforded access for small craniotomies through which the dura was dissected from the frontal bones. An ultrasonic scalpel and endoscope then traveled extradurally to osteotomize the frontal bones, temporal bones, sphenoid wings, and superior aspects of the orbits intracranially. Pterygomaxillary dysjunction was performed with conventional osteotomes intraorally., Results: The endoscopic ultrasonic monobloc osteotomy was completed as a single fragment in all 3 cadavers. No additional incisions were required. Completeness of the osteotomy and integrity of the single fragment were evaluated by manual examination and endoscopic visualization of free movement at osteotomy sites. Osteotomy completion took less than 2.5 hours. Dura and periosteum surrounding all osteotomies remained intact, eliminating concern for injury to adjacent soft tissue. Careful placement of temporal incisions and craniotomies was critical to facilitate completion of osteotomies in a clinically safe manner., Conclusions: We have demonstrated the feasibility of an endoscopic ultrasonic monobloc advancement technique in cadavers. The technique can be completed without a bicoronal incision while completely protecting all vital structures. The preservation of vascularity and periosteum afforded by this technique may provide improved outcomes and reduced complications.
- Published
- 2010
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18. Endoscopically assisted Le Fort III osteotomy using an ultrasonic scalpel: a feasibility study in cadavers.
- Author
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Taylor JA, Maercks RA, Runyan CM, Jones DC, and Gordon CB
- Subjects
- Adult, Cadaver, Cheek surgery, Endoscopy, Eyelids surgery, Feasibility Studies, Female, Humans, Male, Orbit surgery, Zygoma surgery, Maxilla surgery, Osteotomy, Le Fort instrumentation, Osteotomy, Le Fort methods, Ultrasonic Therapy instrumentation
- Abstract
Drawbacks to conventional Le Fort III osteotomy include bleeding, infection, relapse, and scar at the coronal incision. We performed an endoscopically assisted Le Fort III osteotomy with an ultrasonic scalpel in cadavers to develop a new technique that minimizes such complications. Endoscopically assisted Le Fort III osteotomy was performed in 3 fresh, adult human cadavers. Access incisions included the transconjunctival lower lid with lateral canthotomy, the lateral upper gingivobuccal sulcus, and a stab incision in the medial aspect of the upper eyelid. Osteotomies at the zygomaticofrontal suture, the lateral orbital wall, the orbital floor, and the medial orbital wall were carried out with an ultrasonic scalpel under direct and endoscopic visualization from the trasconjunctival incision. The zygomatic arch and the pterygomaxillary region were osteotomized via the upper gingivobuccal sulcus incisions. The nasofrontal junction and the septum were accessed and cut via a stab incision in the medial upper eyelids. Disimpaction was completed with minor digital pressure inferiorly.Each of the 3 Le Fort III osteotomies was complete, and mobility was checked by manual examination. There was a steep learning curve to the operation, but the final cadaver dissection took 99 minutes to complete. The ultrasonic scalpel provided for maximal ease in cutting bone and minimal disruption to adjacent soft tissues as judged by postoperative direct examination. This cadaver study demonstrates the feasibility of a minimally invasive, endoscopically assisted Le Fort III osteotomy using an ultrasonic scalpel. Further experimental work combined with refinements in technique and equipment will help bring this advancement into clinical application.
- Published
- 2009
- Full Text
- View/download PDF
19. Mandibular distraction for micrognathia and severe upper airway obstruction.
- Author
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Mandell DL, Yellon RF, Bradley JP, Izadi K, and Gordon CB
- Subjects
- Case-Control Studies, Child, Preschool, Databases, Factual statistics & numerical data, Female, Humans, Infant, Male, Pierre Robin Syndrome surgery, Tracheotomy, Mandibular Advancement methods, Micrognathism surgery, Osteogenesis, Distraction, Sleep Apnea, Obstructive surgery
- Abstract
Objective: To determine whether the use of mandibular distraction osteogenesis (DOG) can help to avoid tracheotomy or achieve decannulation in patients with mandibular hypoplasia and severe upper airway obstruction., Design: Retrospective medical record review (spanning a 27-month period)., Setting: Tertiary care children's hospital., Subjects: Group A (n=8) was composed of infants with Pierre Robin sequence and no tracheotomy (mean age, 2.5 months); group B (n=6), older nontracheotomized micrognathic children with obstructive sleep apnea (OSA) (mean age, 69 months); and group C (n=12), tracheotomized children with complex congenital syndromes (mean age, 33 months)., Intervention: Bilateral mandibular DOG with endoscopic (n=24) and/or radiographic (n=17) airway evaluation (mean follow-up, 16 months [range, 2-42 months])., Outcome Measures: Group A, tracheotomy avoidance; group B, resolution of OSA (clinically or on polysomnography); and group C, decannulation., Results: Group A, 7 patients (88%) successfully avoided tracheotomy; group B, 5 patients (83%) had resolution of OSA; and group C, 2 patients (17%) underwent decannulation., Conclusions: Mandibular DOG (1) allows tracheotomy avoidance in infants with isolated Pierre Robin sequence and (2) relieves OSA in older micrognathic children without tracheotomy. However, mandibular DOG does not frequently lead to decannulation in tracheotomized patients with complex congenital syndromes.
- Published
- 2004
- Full Text
- View/download PDF
20. Umbilical transposition in TRAM flap: a simple horizontal translocation.
- Author
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Raveh T, Gordon CB, and del Campo AF
- Subjects
- Humans, Abdominal Muscles surgery, Surgical Flaps, Umbilicus surgery
- Abstract
A simple method of umbilical repositioning by incising the anterior rectus sheath and rectus abdominis muscle is reported for cases of unilateral abdominal wall plication during the TRAM flap operation. This method keeps the umbilicus stable and nonstenotic, and it avoids hypertrophic scars, which result from other techniques such as direct suturing of the stalk to the skin. Although this method might weaken contralateral muscle activity, the patients we operated on maintained their ability to perform sit-ups, and no periumbilical weakening was noticed.
- Published
- 1999
- Full Text
- View/download PDF
21. Liposuction: procedure for focal volume reduction and body contour remodeling.
- Author
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Fuente del Campo AF, Rojas Allegretti E, Fernandes Filho JA, and Gordon CB
- Subjects
- Adult, Female, Humans, Lipectomy adverse effects, Middle Aged, Lipectomy methods
- Abstract
Liposuction is the most commonly used procedure for focal reduction of body fat deposits and remodeling the body contour. The procedure consists in aspirating fat from lamellar deposits using a vacuum source connected to a cannula that is passed bluntly through fatty tissue. Adjuncts to the procedure include infiltration of solutions to aid in fat removal or to limit blood loss and the application of ultrasonic energy to lyse fat cells before suction aspiration. Surgical history, theory, procedures, indications, potential complications, and guidelines are discussed herein.
- Published
- 1998
- Full Text
- View/download PDF
22. Regional dermolipectomy as treatment for sequelae of massive weight loss.
- Author
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Fuente del Campo A, Rojas Allegretti E, Fernandez Filho JA, and Gordon CB
- Subjects
- Female, Humans, Male, Dermatologic Surgical Procedures, Lipectomy methods, Surgery, Plastic methods, Weight Loss
- Abstract
Dermolipectomy is the most important procedure for treatment of the deformities engendered by massive weight loss. It remains the only treatment for excising redundant skin. Although liposuction is useful for removing fatty deposits without traditional surgical incisions, its application is limited by the ability of the skin to contract and conform to the newly sculpted figure. Thus liposuction may serve as an adjunct when treating the sequelae of weight loss but not as a primary procedure. In response to changing expectations, reconstructive surgeons have developed increasingly ingenious and specific dermolipectomy procedures to minimize or hide scars, lessen morbidity, and enhance function. Liposuction in combination with dermolipectomy has expanded the applicability of traditional procedures to a wider variety of patients. Surgical history, patient selection, surgical planning, a spectrum of regional dermolipectomy procedures, and potential complications are discussed herein.
- Published
- 1998
- Full Text
- View/download PDF
23. Evolution from endoscopic to miniinvasive facelift: a logical progression?
- Author
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del Campo AF, Gordon CB, and Bergman OK
- Subjects
- Adult, Blepharoplasty methods, Female, Follow-Up Studies, Humans, Laparoscopy methods, Male, Minimally Invasive Surgical Procedures methods, Neck surgery, Postoperative Complications prevention & control, Time Factors, Rhytidoplasty methods
- Abstract
Endoscopy has revolutionized the field of aesthetic surgery, permitting the advent of cosmetic surgery via minimal incisions. The procedures are modifications of subperiosteal lifting techniques which grew out of craniofacial surgery. Nonetheless, the cumbersome instrumentation and changes in operator technique have led to the development of a subperiosteal facelift through minimal incisions without the aid of endoscopy. This miniinvasive approach has yielded equivalent results to our endoscopic rhytidectomies in appropriate patients, with reduced morbidity, edema, and operating time. Further, it permits the avoidance of preauricular scars in the majority (84%) of patients; 63 cases are presented, with a follow-up of up to 4 years.
- Published
- 1998
- Full Text
- View/download PDF
24. Vitreopapillary traction as a cause of elevated optic nerve head.
- Author
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Wisotsky BJ, Magat-Gordon CB, and Puklin JE
- Subjects
- Aged, Aged, 80 and over, Eye Diseases complications, Eye Diseases diagnostic imaging, Female, Fundus Oculi, Humans, Intraocular Pressure, Male, Middle Aged, Optic Disk diagnostic imaging, Optic Nerve Diseases diagnostic imaging, Optic Nerve Diseases pathology, Ultrasonography, Vitreous Body diagnostic imaging, Optic Disk pathology, Optic Nerve Diseases etiology, Vitreous Body pathology
- Abstract
Purpose: To identify vitreopapillary tractional forces as a possible cause of optic nerve head elevation., Methods: Case reports. Two patients aged 64 and 84 years underwent detailed ocular examination and B-scan ultrasonography., Results: Both patients had a unilateral elevated optic nerve head with normal color vision, normal pupillary responses, and full kinetic perimetry. Biomicroscopic and B-scan ultrasonographic evaluation confirmed the presence of vitreopapillary traction., Conclusions: Vitreopapillary traction can cause unilateral optic nerve head elevation. The posterior hyaloid should be evaluated in patients with optic nerve head elevation.
- Published
- 1998
- Full Text
- View/download PDF
25. Angle-closure glaucoma as an initial presentation of systemic lupus erythematosus.
- Author
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Wisotsky BJ, Magat-Gordon CB, and Puklin JE
- Subjects
- Adult, Choroid Diseases diagnostic imaging, Choroid Diseases surgery, Drainage methods, Exudates and Transudates diagnostic imaging, Female, Glaucoma, Angle-Closure etiology, Glaucoma, Angle-Closure surgery, Humans, Intraocular Pressure, Lupus Erythematosus, Systemic complications, Pleural Effusion diagnostic imaging, Radiography, Sclerostomy, Ultrasonography, Glaucoma, Angle-Closure diagnosis, Lupus Erythematosus, Systemic diagnosis
- Abstract
Purpose: To study a patient with bilateral uveal effusions and secondary glaucoma as an initial manifestation of systemic lupus erythematosus., Design: A case report., Methods: The patient presented with bilateral uveal effusions and angle-closure glaucoma. A detailed ocular examination with ultrasonography and a comprehensive medical evaluation with laboratory testing were performed., Results: The ocular examination revealed bilateral uveal effusions with angle-closure and elevated intraocular pressures. A systemic evaluation revealed bilateral pleural effusions and laboratory values consistent with systemic lupus erythematosus. After medical and laser therapy failed to lower the intraocular pressure, partial thickness sclerectomies, linear sclerostomies, and choroidal drainage were successful in controlling the glaucoma., Conclusions: Uveal effusion with secondary glaucoma can be a presenting sign for systemic lupus erythematosus. If antecedent ocular abnormalities are not present, a systemic evaluation is warranted in assessing a patient with uveal effusions and secondary angle-closure glaucoma. Partial-thickness sclerectomies, linear sclerostomies, and choroidal drainage may be effective in lowering intraocular pressure.
- Published
- 1998
- Full Text
- View/download PDF
26. Heat shock protein expression in human placenta and umbilical cord.
- Author
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Li DG, Gordon CB, Stagg CA, and Udelsman R
- Subjects
- Blotting, Western, Female, Humans, Immunohistochemistry, Pregnancy, RNA, Messenger analysis, Heat-Shock Proteins analysis, Placenta metabolism, Umbilical Cord metabolism
- Abstract
We examined the level of heat shock proteins (HSPs) present in umbilical cord vessels and placenta following delivery. A 10 cm segment of fresh umbilical cord was obtained immediately after delivery and a placental biopsy was obtained following the third stage of labor. Apgar scores, cord pHs, and pertinent histories were recorded. Tissues were prepared and analyzed for HSP mRNA by in situ hybridization, Western blot, and immunohistochemistry. Sixteen patients were studied. HSP72 mRNA was selectively expressed in the vascular smooth muscle in all cord arteries and veins. This correlated with marked expression of HSP72 protein in the vascular media. Both HSP72/73 mRNA and protein expression were noted diffusely in the placenta. HSP27 protein was highly expressed in umbilical cords with lower levels present in placentas. There were no correlations between method of delivery, gestational age, Apgar score, cord pH, or fetal outcome to the magnitude or distribution of the HSP response. This is the first demonstration of HSP expression in the human maternal-fetal circulation.
- Published
- 1996
- Full Text
- View/download PDF
27. Impaired wound healing in Cushing's syndrome: the role of heat shock proteins.
- Author
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Gordon CB, Li DG, Stagg CA, Manson P, and Udelsman R
- Subjects
- Adrenal Glands pathology, Animals, Heat-Shock Proteins analysis, Immunohistochemistry, Male, Organ Size, Rats, Rats, Wistar, Cushing Syndrome physiopathology, Heat-Shock Proteins physiology, Wound Healing
- Abstract
Background: Glucocorticoids impair wound healing and cause surgical morbidity. Heat shock proteins are essential to cellular stress tolerance and are associated with glucocorticoids. The adrenal heat shock protein response is under hypothalmic-pituitary-adrenal-axis control, whereas the vascular response is associated with alpha-1 receptors. Because heat shock proteins affect cellular stress responses and are under hypothalmic-pituitary-adrenal-axis control in other tissues, we postulated an association between heat shock proteins and glucocorticoids in healing wounds., Methods: Modified Hunt-Schilling wound chambers were implanted subcutaneously in rats. They received subcutaneous time-release dexamethasone (25 mg) or placebo pellets. Wound chamber heat shock protein 25 and heat shock protein 72/73 were serially assayed for 21 days with western analysis and immunocytochemistry., Results: Dexamethasone caused Cushing's syndrome with approximately 10% weekly weight-loss and adrenal atrophy. Total wound tissue decreased 90% with profound differences in molecular wound responses manifested by decreased heat shock protein 25, 72, and 73 in animals treated with dexamethasone despite equal protein loads. Furthermore, dexamethasone caused heat shock protein 72 redistribution by immunocytochemistry., Conclusions: This study represents the first description of heat shock proteins in a wound healing model and demonstrates tissue-specific decrease of heat shock proteins with glucocorticoid therapy. Thus the heat shock protein response is intimately associated with normal wound healing and is profoundly altered in subjects with Cushing's syndrome. Manipulation of this response may have clinical importance in wound healing.
- Published
- 1994
28. Adrenergic regulation of adrenal and aortic heat shock protein.
- Author
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Udelsman R, Li DG, Stagg CA, Gordon CB, and Kvetnansky R
- Subjects
- Animals, Epinephrine metabolism, Male, Norepinephrine metabolism, Rats, Rats, Wistar, Adrenal Glands metabolism, Aorta metabolism, Heat-Shock Proteins genetics, RNA, Messenger analysis, Receptors, Adrenergic, alpha-1 physiology
- Abstract
Background: Surgical stress results in catecholamine secretion and selective induction of the major heat shock protein (HSP70) in the adrenal gland and in the vasculature. The adrenal response is cortical-specific and corticotropin-dependent. The vascular response occurs in the smooth muscle and is corticotropin-independent. We previously suggested that the vascular response was associated with adrenergic receptor stimulation. Herein, we report a series of experiments designed to test the hypothesis that aortic HSP70 messenger RNA (mRNA) induction occurs as a direct and specific response to alpha 1-adrenergic receptor stimulation., Methods: Acute and chronic indwelling central venous catheter models were developed in the Wistar rat through which the following agents were infused: the alpha 1 agonist phenylephrine (0.14 mg/kg), the beta agonist isoproterenol (0.8 mg/kg), the alpha 1 antagonist prazosin (1 mg/kg), prazosin followed by phenylephrine, or saline solution alone. Hemodynamic responses were monitored; catecholamines were measured by high-performance liquid chromatography; 60 minutes after infusion, the animals were killed, and the adrenal glands and aortas were assayed for HSP70 mRNA expression on Northern blots., Results: Alpha 1 stimulation with phenylephrine resulted in marked hypertension, a reflexive bradycardia, and marked induction of aortic HSP70 mRNA. This effect could be completely abolished when the alpha 1 antagonist prazosin was administered before phenylephrine treatment. The beta agonist isoproterenol failed to induce aortic HSP70. A significant catecholamine response only occurred after prazosin administration., Conclusions: These studies show a functional interaction between alpha 1 receptor stimulation and vascular HSP mRNA induction.
- Published
- 1994
29. Identification and purification of a factor that binds to the Mlu I cell cycle box of yeast DNA replication genes.
- Author
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Verma R, Patapoutian A, Gordon CB, and Campbell JL
- Subjects
- Base Sequence, Carrier Proteins isolation & purification, Cell Cycle genetics, Cell Nucleus physiology, DNA Polymerase I genetics, Deoxyribonuclease I, Deoxyribonucleases, Type II Site-Specific, Fungal Proteins genetics, Molecular Sequence Data, Oligonucleotide Probes, Restriction Mapping, Saccharomyces cerevisiae cytology, Saccharomyces cerevisiae metabolism, Transcription, Genetic, Bacterial Proteins, Carrier Proteins metabolism, DNA Replication, Genes, Fungal, Saccharomyces cerevisiae genetics
- Abstract
In Saccharomyces cerevisiae, the genes encoding at least 10 enzymes involved in DNA replication are periodically expressed in the late G1 and S phases of the cell cycle. All of these genes have one copy or more of the sequence ACGCGT, which conforms to the recognition site for the Mlu I restriction endonuclease. For the CDC21, CDC9, and POL1 genes, the Mlu I site has been shown to be absolutely required for periodic transcription. Using nuclear extracts fractionated by conventional and oligonucleotide affinity chromatography, we have purified a 17-kDa protein that recognizes the Mlu I motif. Synthetic oligonucleotides containing mutated Mlu I sites do not bind the protein. In contrast, synthetic oligonucleotides derived from the CDC2, CDC6, and CDC21 genes, which are expressed with the same timing as POL1, bind purified protein efficiently.
- Published
- 1991
- Full Text
- View/download PDF
30. A cell cycle-responsive transcriptional control element and a negative control element in the gene encoding DNA polymerase alpha in Saccharomyces cerevisiae.
- Author
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Gordon CB and Campbell JL
- Subjects
- Base Sequence, Cell Cycle, Chromosome Deletion, Gene Expression Regulation, Enzymologic, Gene Expression Regulation, Fungal, Molecular Sequence Data, Oligonucleotide Probes, Restriction Mapping, Saccharomyces cerevisiae cytology, Saccharomyces cerevisiae enzymology, TATA Box, DNA Polymerase II genetics, Genes, Fungal, Promoter Regions, Genetic, Saccharomyces cerevisiae genetics, Transcription, Genetic
- Abstract
Transcription of the POL1 gene of Saccharomyces cerevisiae, which encodes DNA polymerase alpha, the DNA polymerase required for the initiation of DNA replication, has previously been shown to be cell cycle regulated. To understand how the POL1 gene senses cell cycle position, we have investigated the cis-acting elements that respond to the factors that govern cell cycle progression. In this report we demonstrate that a region of 54 nucleotides containing the repeated element ACGCGT, which conforms to an Mlu I restriction endonuclease recognition site, contains all information necessary for transcriptional activation and cell cycle responsiveness. Although oligonucleotides lacking either one or both of the repeated Mlu I sites can function as an upstream activating sequence, the presence of at least one Mlu I site stimulates expression and, moreover, is absolutely essential for cell cycle regulation. A synthetic oligonucleotide corresponding to a 19-base-pair sequence in the POL1 promoter containing one Mlu I site can function as an autonomous cell cycle-responsive upstream element (upstream activation sequence) with temporal regulation indistinguishable from that previously described for the POL1 gene. Thus, the Mlu I site is an essential part of a cis-acting element responsible for the observed periodic activation. This sequence differs from previously defined cell cycle-responsive transcriptional control elements in the yeast HO endonuclease and histone genes. We also present evidence for a negative regulatory element in the 5' flanking region of the Mlu I upstream activation sequence.
- Published
- 1991
- Full Text
- View/download PDF
31. The cdc22 gene of Schizosaccharomyces pombe encodes a cell cycle-regulated transcript.
- Author
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Gordon CB and Fantes PA
- Abstract
Two independent DNA sequences, of 5.6 and 2.4 kb in size, were isolated from Schizosaccharomyces pombe gene libraries on the basis of their ability to rescue the temperature-conditional lethality conferred by a cdc22 mutation. Integration of these sequences into the S.pombe genome by homologous recombination, followed by genetic mapping, demonstrated that the site of integration of the 5.6 kb fragment is tightly linked to the cdc22 locus, while that of the 2.4 kb fragment is unlinked. This shows that the 5.6 kb fragment carries the authentic cdc22 gene while the 2.4 kb fragment carries and extragenic suppressor sequence. The cdc22 transcript was identified by Northern blot analysis and shown to be 3.3 kb in size. The level of the transcript during the cell cycle was investigated in synchronous cultures prepared by elutriation. The cdc22 transcript is cell cycle regulated, reaching a maximum level during late G1/S phase, at least 12-fold higher than the minimum level observed in mid G2.
- Published
- 1986
- Full Text
- View/download PDF
32. Practical approach to the loss of smell.
- Author
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Gordon CB
- Subjects
- Central Nervous System Diseases complications, Environmental Exposure, Humans, Nasopharyngeal Diseases complications, Olfaction Disorders etiology, Olfaction Disorders genetics, Virus Diseases complications, Olfaction Disorders diagnosis
- Abstract
Loss of the sense of smell can be easily confirmed in any physician's office by having the patient try to identify various odors. The etiology of anosmia can be extremely varied, including nasopharyngeal disorders such as rhinitis and tumors; neurologic conditions such as head trauma, neoplasms, vascular lesions and infections of the central nervous system; viral infections; familial and congenital disorders; drugs; industrial exposure; endocrine diseases, and several other disorders. The prognosis of anosmia is guarded, and its treatment depends on the etiology.
- Published
- 1982
33. Ga-67-citrate and ultrasonographic visualization of genitourinary tuberculosis.
- Author
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Leventhal WD, Gordon CB, and Hotchkiss S
- Subjects
- Abscess diagnostic imaging, Adolescent, Endometrium, Female, Humans, Kidney, Radionuclide Imaging, Salpingitis diagnostic imaging, Gallium Radioisotopes, Tuberculosis, Urogenital diagnostic imaging, Ultrasonography
- Published
- 1981
- Full Text
- View/download PDF
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