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2.
Plast Reconstr Surg ; 140(6): 1169-1184, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28806294

ABSTRACT

BACKGROUND: Suboptimal healing of the tendon-bone interface remains an unsolved problem. The authors hypothesized that (1) platelet-rich plasma and prolonged in vitro incubation will produce interface scaffolds with greater reseeding of viable adipose-derived stem cells; and (2) when implanted with extracellular matrix hydrogel, constructs will display superior in vivo strength repair and biocompatibility. METHODS: Achilles-calcaneal composite tendon-bone interface scaffold grafts were harvested from 30 Wistar rats. After physicochemical decellularization and lyophilization, scaffolds were revitalized in rat plasma or 100% activated rat platelet-rich plasma and reseeded with viable adipose-derived stem cells. For part 2 of the study, 90 Sprague-Dawley rats underwent reconstruction with one of five decellularized, lyophilized scaffold revitalization/reseeding conditions: (1) phosphate-buffered saline; (2) lyophilized, 100% activated platelet-rich plasma; (3) platelet-rich plasma and extracellular matrix hydrogel; (4) platelet-rich plasma and 14-day reseeding with ASC-luc2-eGFP cells; and (5) plasma, reseeding, and hydrogel. RESULTS: In part 1, platelet-rich plasma-revitalized grafts demonstrated greater live viable adipose-derived stem cell loads at 3, 7, and 14 days and total adipose-derived stem cell loads at 7 and 14 days with visibly greater live surface cellularity, layering, migration, and penetration. In part 2, bioluminescence imaging confirmed cell viability to day 22 after implantation. Biomechanical strength testing demonstrated a significant increase in ultimate failure load for reseeded groups compared with all other groups at week 2, whereas only reseeded grafts with hydrogel remained significantly stronger at weeks 4 and 8. Histologic examination demonstrated most increased tendinous cellular invasion and fibrocartilage repopulation at 8 weeks in the reseeded group with hydrogel. Masson trichrome staining demonstrated persistence of the scaffold structure at week 8 and blinded ImageJ analysis demonstrated significantly more type III collagen in the reseeded/hydrogel group at 2, 4, and 8 weeks. CONCLUSIONS: Decellularized lyophilized allogeneic tendon-bone interface scaffolds can be optimized by revitalization in platelet-rich plasma, reseeding with viable adipose-derived stem cells, and supplemented by an extracellular matrix tendon hydrogel at the time of implantation. When this is done, they display greater repair strength and biocompatibility.


Subject(s)
Achilles Tendon/transplantation , Adipocytes/physiology , Calcaneus/physiology , Platelet-Rich Plasma , Stem Cells/physiology , Tissue Engineering , Achilles Tendon/physiology , Animals , Extracellular Matrix/physiology , Graft Survival , Hydrogel, Polyethylene Glycol Dimethacrylate/pharmacology , Rats, Sprague-Dawley , Rats, Wistar , Tissue Scaffolds , Wound Healing/physiology
3.
Ann Plast Surg ; 78(5 Suppl 4): S243-S247, 2017 May.
Article in English | MEDLINE | ID: mdl-28399026

ABSTRACT

BACKGROUND: Music is commonly played in operating rooms (ORs) throughout the country. If a preferred genre of music is played, surgeons have been shown to perform surgical tasks quicker and with greater accuracy. However, there are currently no studies investigating the effects of music on microsurgical technique. Motion analysis technology has recently been validated in the objective assessment of plastic surgery trainees' performance of microanastomoses. Here, we aimed to examine the effects of music on microsurgical skills using motion analysis technology as a primary objective assessment tool. METHODS: Residents and fellows in the Plastic and Reconstructive Surgery program were recruited to complete a demographic survey and participate in microsurgical tasks. Each participant completed 2 arterial microanastomoses on a chicken foot model, one with music playing, and the other without music playing. Participants were blinded to the study objectives and encouraged to perform their best. The order of music and no music was randomized. Microanastomoses were video recorded using a digitalized S-video system and deidentified. Video segments were analyzed using ProAnalyst motion analysis software for automatic noncontact markerless video tracking of the needle driver tip. RESULTS: Nine residents and 3 plastic surgery fellows were tested. Reported microsurgical experience ranged from 1 to 10 arterial anastomoses performed (n = 2), 11 to 100 anastomoses (n = 9), and 101 to 500 anastomoses (n = 1). Mean age was 33 years (range, 29-36 years), with 11 participants right-handed and 1 ambidextrous. Of the 12 subjects tested, 11 (92%) preferred music in the OR. Composite instrument motion analysis scores significantly improved with playing preferred music during testing versus no music (paired t test, P <0.001). Improvement with music was significant even after stratifying scores by order in which variables were tested (music first vs no music first), postgraduate year, and number of anastomoses (analysis of variance, P < 0.01). CONCLUSIONS: Preferred music in the OR may have a positive effect on trainees' microsurgical performance; as such, trainees should be encouraged to participate in setting the conditions of the OR to optimize their comfort and, possibly, performance. Moreover, motion analysis technology is a useful tool with a wide range of applications for surgical education and outcomes optimization.


Subject(s)
Clinical Competence , Microsurgery , Music , Surgery, Plastic/education , Time and Motion Studies , Adult , Anastomosis, Surgical , Fellowships and Scholarships , Female , Humans , Internship and Residency , Male , Operating Rooms , Surveys and Questionnaires , Video Recording
4.
Ann Plast Surg ; 76 Suppl 3: S249-54, 2016 May.
Article in English | MEDLINE | ID: mdl-27070681

ABSTRACT

INTRODUCTION: The choice to undergo mastectomy and breast reconstruction is a highly personal decision with profound psychosocial effects, and ultimately, the decision between implant- and autologous tissue-based reconstruction should be made based on a combination of factual information and the patient's personal values and preferences. Unfortunately, patients undergoing breast reconstruction surgery may experience decision regret. Decision aids promote patient involvement in decision making by not only providing standard information about options, but also emphasizing comparative risks, benefits, and alternatives, and most importantly by providing clarification exercises regarding personal values to guide patients toward an individualized decision. METHODS: We developed a novel decision aid to provide decision support and structured guidance for prosthetic, autologous, and combined prosthetic-autologous breast reconstruction surgery. New breast reconstruction patients of one surgeon at our institution were randomized by week to either receive the decision aid or standard preconsultation material. Immediately preceding their new patient consultation clinic visit, patients were asked to complete the validated Decisional Conflict Scale and the BREAST-Q Preoperative survey. After 3 to 5 months following breast mound reconstruction, patients were asked to complete the Decision Regret Scale, BREAST-Q Postoperative survey, and the Hospital Anxiety and Depression Scale. RESULTS: Patients who received the decision aid demonstrated a trend toward decreased preoperative decisional conflict (mean of 13.3 ± 5.5, compared to 26.2 ± 4.2; n = 8 per group, P = 0.069), with similar preoperative BREAST-Q scores. Most patients desired to know "everything" regarding their reconstruction surgery (75%), and to be "very involved" in the decisions in their care (81%), with remaining patients wanting to know "as much as I need to be prepared" and to be "somewhat involved." Postoperatively, patients who received the decision aid demonstrated significantly less decision regret (P < 0.001), although there was no significant difference in anxiety, depression, or quality of life-related outcomes as measured by the BREAST-Q. CONCLUSIONS: The use of decision aids in breast reconstruction surgery may help decrease decisional conflict and regret through promoting improved information sharing and shared decision making, which are highly important in this particular setting, patient population, and in our move toward greater patient-centered care.


Subject(s)
Decision Support Techniques , Mammaplasty/psychology , Mastectomy/psychology , Patient Participation/methods , Patient Satisfaction/statistics & numerical data , Patient-Centered Care/methods , Adult , Female , Follow-Up Studies , Humans , Mammaplasty/methods , Middle Aged , Outcome and Process Assessment, Health Care , Patient Participation/psychology , Prospective Studies
5.
Ann Plast Surg ; 77(1): 47-53, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25305229

ABSTRACT

PURPOSE: Previous work has characterized the development of a human tendon hydrogel capable of improving mechanical strength after tendon injury. Animal tendon hydrogel has not yet been described, but would prove beneficial due to the cost and ethical concerns associated with the use of human cadaveric tendon. This study details the manufacture and assesses the biocompatibility of porcine tendon hydrogel seeded with human adipoderived stem cells (ASCs). MATERIALS AND METHODS: Porcine tendon was dissected from surrounding connective and muscle tissue and decellularized via 0.2% sodium dodecyl sulfate and 0.2% sodium dodecyl sulfate/ethylenediaminetetraacetic acid wash solutions before lyophilization. Tendon was milled and reconstituted by previously described methods. Decellularization was confirmed by hematoxylin-eosin staining, SYTO Green 11 nucleic acid dye, and DNeasy assay. The protein composition of milled tendon matrix before and after digestion was identified by mass spectrometry. Rheological properties were determined using an ARG2 rheometer. Biocompatibility was assessed by live/dead assay. The proliferation of human ASCs seeded in porcine and human hydrogel was measured by MTS assay. All experimental conditions were performed in triplicate. RESULTS: Decellularization of porcine tendon was successful. Mass spectrometry showed that collagen composes one third of milled porcine tendon before and after pepsin digestion. Rheology demonstrated that porcine hydrogel maintains a fluid consistency over a range of temperatures, unlike human hydrogel, which tends to solidify. Live/dead staining revealed that human ASCs survive in hydrogel 7 days after seeding and retain spindle-like morphology. MTS assay at day 3 and day 5 showed that human ASC proliferation was marginally greater in human hydrogel. CONCLUSIONS: After reconstitution and digestion, porcine hydrogel was capable of supporting growth of human ASCs. The minimal difference in proliferative capacity suggests that porcine tendon hydrogel may be an effective and viable alternative to human hydrogel for the enhancement of tendon healing.


Subject(s)
Biocompatible Materials , Guided Tissue Regeneration/methods , Hydrogel, Polyethylene Glycol Dimethacrylate , Regeneration/physiology , Tendon Injuries/surgery , Tendons/physiology , Tissue Scaffolds , Animals , Humans , Mesenchymal Stem Cell Transplantation , Swine , Tendons/surgery
6.
Plast Reconstr Surg ; 136(2): 231e-240e, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26218398

ABSTRACT

BACKGROUND: Evaluation of skill acquisition in microsurgery has traditionally relied on subjective opinions of senior faculty, but is shifting toward early competency-based training using validated models. No objective measures of dexterity, economy of movement, and ability exist. The authors propose a novel video instrument motion analysis scoring system to objectively measure motion. METHODS: Video of expert microsurgeons was analyzed and used to develop a resident motion analysis scoring system based on a mathematical model. Motion analysis scores were compared to blinded, global rating scores of the same videos using the Stanford Microsurgery and Resident Training scale. RESULTS: Eighty-five microsurgical anastomoses from 16 residents ranging from postgraduate years 1 through 6 were analyzed. Composite motion analysis scores for each segmented video correlated positively to arterial anastomotic experience (rho, +0.77; p < 0.001). Stanford Microsurgery and Resident Training scale interrater reliability was consistent between expert assessors, and mean composite motion analysis overall performance and Stanford scores were well matched for each level of experience. Composite motion analysis scores correlated significantly with combined Stanford Microsurgery and Resident Training [instrument handling (rho, +0.66; p < 0.01), efficiency (rho, +0.59; p < 0.01), suture handling (rho, +0.83; p < 0.001), operative flow (rho, +0.67; p < 0.001), and overall performance (rho, +89; p < 0.001)] motion components of the scale. CONCLUSIONS: Instrument motion analysis provides a novel, reliable, and consistent objective assessment for microsurgical trainees. It has an associated cost, but is timely, repeatable, and senior physician independent, and exposes patients to zero risk.


Subject(s)
Clinical Competence , Education, Medical, Graduate/methods , Internship and Residency/organization & administration , Microsurgery/education , Time and Motion Studies , Adult , California , Cohort Studies , Educational Measurement/methods , Female , Humans , Male , Observer Variation , Reproducibility of Results , Task Performance and Analysis , Video Recording
7.
Eplasty ; 15: e24, 2015.
Article in English | MEDLINE | ID: mdl-26171096

ABSTRACT

OBJECTIVE: To design, develop, and evaluate via focus group a preconsultation decision aid to improve patient satisfaction for breast reconstruction. METHODS: The design of the decision aid was based on perceived patient needs, literature, existing decision aids, and current standard of breast cancer reconstruction treatment and consultation at Stanford. Our decision aid was designed to (1) reducing fear of the unknown in patients via providing a knowledge base that they can rely on, (2) helping patients identify their key breast reconstruction concerns, (3) addressing common patient concerns, (4) providing a framework to help patients identify the treatment option that may be right for them, and (5) promoting shared decision making. Physicians were consulted on the decision aid, following which a focus group was conducted for patient feedback. RESULTS: Interviewed patients (n = 12) were supportive of the decision aid initiative. Participants were especially pleased with the side-by-side comparison of surgical options and the parsimonious way information was represented. All patients before undergoing reconstruction (n = 3) requested the decision guide to reference at home. All interviewed patients believed information level was "about right." CONCLUSIONS: Decision aid was well received by patients in the focus group. As the initiative is for quality improvement, we saw no need to further delay the distribution of the decision aid. A pilot study will be conducted to evaluate whether our decision aid has an effect on patients' decision regret, stress, and anxiety.

8.
Plast Reconstr Surg ; 135(6): 981e-989e, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26017614

ABSTRACT

BACKGROUND: Tendon hydrogel is a promising new injectable substance that has been shown to improve repair strength after tendon injury. This study assesses the capacity of platelet-rich plasma to stimulate proliferation and migration of rat adipose-derived stem cells in tendon hydrogel in vitro. METHODS: To assess proliferation, adipose-derived stem cells were exposed to plasma, plasma supplemented with growth factors, or platelet-rich plasma in culture medium and tendon hydrogel. To assess migration, adipose-derived stem cells were plated onto tendon hydrogel -coated wells and covered with medium containing plasma, plasma supplemented with growth factors, platelet-rich plasma, or bovine serum albumin. Migration from cell-seeded to cell-free zones was assessed at 12-hour intervals. RESULTS: Platelet-rich plasma augmented proliferation to a greater extent compared with plasma and plasma supplemented with growth factors (10%: optical density, 1.18 versus 0.75 versus 0.98, respectively). Platelet-rich plasma was superior to plasma in tendon hydrogel (10%: optical density, 1.19 versus 0.85) but did not augment proliferation to the extent that plasma supplemented with growth factors did (10%: optical density, 1.19 versus 1.56). Platelet-rich plasma enhanced the migration of adipose-derived stem cells compared with serum-free medium (bovine serum albumin) (36 hours: platelet-rich plasma, 1.88; plasma, 1.51; plasma plus growth factor, 1.80; bovine serum albumin, 1.43). CONCLUSIONS: Tendon healing is mediated by migration of cells to the injured area and cellular proliferation at that site. Tendon hydrogel supplemented with platelet-rich plasma stimulates these processes. Future studies will evaluate this combination's ability to stimulate healing in chronic tendon injuries in vivo.


Subject(s)
Adipocytes/transplantation , Hydrogel, Polyethylene Glycol Dimethacrylate/pharmacology , Platelet-Rich Plasma , Regeneration/physiology , Tendons/physiology , Animals , Cell Proliferation/drug effects , Cells, Cultured , Culture Media , In Vitro Techniques , Models, Animal , Random Allocation , Rats , Rats, Sprague-Dawley , Reference Values , Sensitivity and Specificity , Stem Cells/cytology , Stem Cells/physiology , Tendons/surgery
9.
Tissue Eng Part A ; 21(9-10): 1579-86, 2015 May.
Article in English | MEDLINE | ID: mdl-25625433

ABSTRACT

INTRODUCTION: Acute and chronic tendon injuries would benefit from stronger and more expeditious healing. We hypothesize that supplementation of a biocompatible tendon hydrogel with platelet-rich plasma (PRP) and adipose-derived stem cells (ASCs) would augment the tendon healing process. MATERIALS AND METHODS: Using 55 Wistar rats, a full-thickness defect was created within the midsubstance of each Achilles tendon with the addition of one of five experimental conditions: (i) saline control (50-µL), (ii) tendon hydrogel (50-µL), (iii) tendon hydrogel (45-µL)+PRP (5-µL), (iv) tendon hydrogel (45-µL)+2×10(6)-ASCs/mL in phosphate buffered saline (5-µL), and (v) tendon hydrogel (45-µL)+2×10(6)-ASCs/mL in PRP (5-µL). Hydrogel was developed from decellularized, human cadaveric tendons. Fresh rat PRP was obtained per Amable et al.'s technique, and green fluorescent protein/luciferase-positive rat ASCs were utilized. Rats were sacrificed at weeks 1, 2, 4, and 8 after injury. Real-time in vivo bioluminescence imaging of groups with ASCs was performed. Upon sacrifice, Achilles tendons underwent biomechanical and histological evaluation. Comparisons across groups were analyzed using the two-sample Z-test for proportions and the Student's t-test for independent samples. Significance was set at p<0.05. RESULTS: (i) Bioluminescence imaging demonstrated that total photon flux was significantly increased for hydrogel+PRP+ASCs, versus hydrogel+ASCs for each postoperative day imaged (p<0.03). (ii) Mean ultimate failure load (UFL) was increased for hydrogel augmented with PRP and/or ASCs versus hydrogel alone at week 2 (p<0.03). By week 4, hydrogel alone reached a similar mean UFL to hydrogel augmented with PRP and/or ASCs (p>0.3). However, at week 8, hydrogel with PRP and ASCs demonstrated increased strength over other groups (p<0.05), except for hydrogel with PRP (p=0.25). (iii) Upon histological analysis, Hematoxylin and Eosin staining showed increased extracellular matrix formation in groups containing PRP and increased cellularity in groups containing ASCs. Groups containing both PRP and ASCs demonstrated both of these characteristics. CONCLUSION: PRP and ASCs are easily accessible bioactive products that have potentiating effects on tendon hydrogel. Augmentation with these two factors encourages earlier mechanical strength and functional restoration. Thus, biochemically, tendon hydrogel augmented with PRP and/or ASCs, serves as a promising therapeutic modality for augmenting the tendon healing process after injury.


Subject(s)
Adipose Tissue/cytology , Hydrogel, Polyethylene Glycol Dimethacrylate/pharmacology , Platelet-Rich Plasma/metabolism , Stem Cell Transplantation , Stem Cells/cytology , Tendons/pathology , Wound Healing/drug effects , Animals , Biomechanical Phenomena/drug effects , Elastic Modulus/drug effects , Humans , Imaging, Three-Dimensional , Injections , Luminescent Measurements , Rats, Wistar , Staining and Labeling , Stem Cells/drug effects , Stem Cells/metabolism , Tendon Injuries/pathology , Tendon Injuries/physiopathology , Tendon Injuries/therapy , Tendons/drug effects , Tendons/physiopathology , Weight-Bearing
10.
Hand Clin ; 30(3): 305-17, vi, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25066849

ABSTRACT

This article focuses on the initial steps of commercial development of a patentable scientific discovery from an academic center through to marketing a clinical product. The basics of partnering with a technology transfer office (TTO) and the complex process of patenting are addressed, followed by a discussion on marketing and licensing the patent to a company in addition to starting a company. Finally, the authors address the basic principles of obtaining clearance from the Food and Drugs Administration, production in a good manufacturing practice (GMP) facility, and bringing the product to clinical trial.


Subject(s)
Device Approval , Hand/surgery , Licensure , Marketing of Health Services/organization & administration , Patents as Topic , Technology Transfer , Humans , United States
11.
J Plast Reconstr Aesthet Surg ; 67(7): 967-72, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24838275

ABSTRACT

BACKGROUND AND AIM: Traditional visualization techniques in microsurgery require strict positioning in order to maintain the field of visualization. However, static posturing over time may lead to musculoskeletal strain and injury. Three-dimensional high-definition (3DHD) visualization technology may be a useful adjunct to limiting static posturing and improving ergonomics in microsurgery. In this study, we aimed to investigate the benefits of using the 3DHD technology over traditional techniques. METHODS: A total of 14 volunteers consisting of novice and experienced microsurgeons performed femoral anastomoses on male Sprague-Dawley retired breeder rats using traditional techniques as well as the 3DHD technology and compared the two techniques. Participants subsequently completed a questionnaire regarding their preference in terms of operational parameters, ergonomics, overall quality, and educational benefits. Efficiency was also evaluated by mean times to complete the anastomosis with each technique. RESULTS: A total of 27 anastomoses were performed, 14 of 14 using the traditional microscope and 13 of 14 using the 3DHD technology. Preference toward the traditional modality was noted with respect to the parameters of precision, field adjustments, zoom and focus, depth perception, and overall quality. The 3DHD technique was preferred for improved stamina and less back and eye strain. Participants believed that the 3DHD technique was the better method for learning microsurgery. Longer mean time of anastomosis completion was noted in participants utilizing the 3DHD technique. CONCLUSIONS: The 3DHD technology may prove to be valuable in improving proper ergonomics in microsurgery. In addition, it may be useful in medical education when applied to the learning of new microsurgical skills. More studies are warranted to determine its efficacy and safety in a clinical setting.


Subject(s)
Attitude of Health Personnel , Imaging, Three-Dimensional , Microsurgery/methods , Microvessels/surgery , Musculoskeletal Diseases/etiology , Occupational Diseases/etiology , Vascular Surgical Procedures/methods , Anastomosis, Surgical/education , Anastomosis, Surgical/methods , Animals , Ergonomics , Femoral Artery/surgery , General Surgery , Humans , Internship and Residency , Male , Microsurgery/education , Posture , Rats , Rats, Sprague-Dawley , Students, Medical , Surgery, Plastic , Surveys and Questionnaires , Vascular Surgical Procedures/education
12.
Eur J Public Health ; 23(2): 257-62, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22383477

ABSTRACT

BACKGROUND: Vaccination is an important preventive measure for preparing against the influenza pandemics. This study investigated the attitudes and perceptions of influenza vaccination among doctors and medical students in Hong Kong. METHODS: A cross-sectional survey was conducted among 204 doctors and 242 medical students in a teaching hospital in 2009. Participants' demographic and job characteristics, and influenza experience and vaccination in the previous year were assessed in the questionnaire. Logistic regression models were used to examine the associations between uptake of influenza vaccination and the perceived benefits. RESULTS: Medical students were more likely to have receive an influenza vaccination in the previous year (66.9 vs. 39.7%) and acknowledged the related benefits than doctors. Moreover, uptake of influenza vaccine was associated with perceived benefits of vaccination in both doctors and medical students. CONCLUSIONS: The perceived benefits of influenza vaccination are an important factor in vaccine uptake for both doctors and medical students in Hong Kong, and should be reinforced in the professional training.


Subject(s)
Influenza Vaccines , Influenza, Human/prevention & control , Physicians/psychology , Students, Medical/psychology , Vaccination/statistics & numerical data , Adult , Attitude of Health Personnel , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice , Hong Kong/epidemiology , Hospitals, Teaching , Humans , Influenza, Human/epidemiology , Male , Middle Aged , Pandemics/prevention & control , Perception , Prevalence , Socioeconomic Factors , Surveys and Questionnaires , Vaccination/psychology , Young Adult
13.
Hum Genet ; 131(1): 67-76, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21706185

ABSTRACT

Hirschsprung disease (HSCR, congenital colon aganglionosis) is a relatively common complex genetic condition caused by abnormal development of the enteric nervous system (ENS). Through a recent genome-wide association study conducted on Chinese HSCR patients, we identified a new HSCR contributing locus, neuregulin 1 (NRG1; 8p12), a gene known to be involved in the development of the ENS. As genes in which disease-associated common variants are found are to be considered as candidates for the search of deleterious rare variants (RVs) in the coding sequences, we sequenced the NRG1 exons of 358 sporadic HSCR patients and 333 controls. We identified a total of 13 different heterozygous RVs including 8 non-synonymous (A28G, E134K, V266L, H347Y, P356L, V486M, A511T, P608A) and 3 synonymous amino acid substitutions (P24P, T169T, L483L), a frameshift (E239fsX10), and a c.503-4insT insertion. Functional analysis of the most conserved non-synonymous substitutions, H347Y and P356L, showed uneven intracellular distribution and aberrant expression of the mutant proteins. Except for T169T and V486M, all variants were exclusive to HSCR patients. Overall, there was a statistically significant over-representation of NRG1 RVs in HSCR patients (p = 0.008). We show here that not only common, but also rare variants of the NRG1 gene contribute to HSCR. This strengthens the role of NRG1.


Subject(s)
Hirschsprung Disease/genetics , Mutation/genetics , Neuregulin-1/genetics , Animals , COS Cells , Case-Control Studies , Chlorocebus aethiops , DNA Mutational Analysis , Female , Genome-Wide Association Study , Genotype , Humans , Immunoblotting , Immunoenzyme Techniques , Male
15.
J Heart Lung Transplant ; 30(6): 698-706, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21435906

ABSTRACT

BACKGROUND: Chronic rejection can prevent long-term survival of organ transplants. Although the beneficial effects of peroxisome proliferator-activated receptor-gamma (PPAR-γ) in reducing graft rejection have been reported, the details of the underlying mechanisms remain unclear, especially in the context of modulating cellular infiltration and preventing vasculopathy and interstitial fibrosis. METHODS: The therapeutic effects of the PPAR-γ agonist, rosiglitazone, combined with anti-interleukin-5 are explored in a mouse model of MHC Class II-histoincompatible cardiac transplantation. RESULTS: Rosiglitazone treatment alone marginally increased long-term survival and reduced CD8 T-cell infiltration and vasculopathy in the grafts. However, there was no reduction in collagen deposition and interleukin (IL)-4, IL-5 and eosinophil infiltration were increased. Anti-IL-5 antibody treatment alone reduced eosinophil infiltration and collagen deposition, but had no effect on CD8 T-cell infiltration or vasculopathy. Combined treatment with anti-IL-5 antibody and rosiglitazone prevented graft rejection. Furthermore, rosiglitazone treatment increased adiponectin receptor II expression in grafts and on dendritic cells and T cells in vitro. Graft survival correlated with increased expression in grafts of the inhibitory molecule PD-L1. CONCLUSIONS: The findings obtained increase the knowledge on the mode of action of rosiglitazone in promoting the survival of MHC Class II-mismatched cardiac transplants in which the CD8 T cells and eosinophils play key roles. PPAR-γ signaling combined with IL-5 blockade prevents graft rejection.


Subject(s)
Graft Rejection/prevention & control , Heart Transplantation/immunology , Immunosuppressive Agents/therapeutic use , Interleukin-5/antagonists & inhibitors , Thiazolidinediones/therapeutic use , Animals , CD8-Positive T-Lymphocytes/immunology , Eosinophils/immunology , Genes, MHC Class II , Graft Rejection/immunology , Graft Survival , Immunosuppressive Agents/pharmacology , Male , Mice , Mice, Inbred C57BL , PPAR gamma/agonists , PPAR gamma/physiology , Rosiglitazone , Signal Transduction/drug effects , Thiazolidinediones/pharmacology
16.
PLoS One ; 5(6): e10918, 2010 Jun 02.
Article in English | MEDLINE | ID: mdl-20532249

ABSTRACT

BACKGROUND: Hirschsprung's disease (HSCR) is a congenital disorder associated with the lack of intramural ganglion cells in the myenteric and sub-mucosal plexuses along varying segments of the gastrointestinal tract. The RET gene is the major gene implicated in this gastrointestinal disease. A highly recurrent mutation in RET (RET(R114H)) has recently been identified in approximately 6-7% of the Chinese HSCR patients which, to date, has not been found in Caucasian patients or controls nor in Chinese controls. Due to the high frequency of RET(R114H) in this population, we sought to investigate whether this mutation may be a founder HSCR mutation in the Chinese population. METHODOLOGY AND PRINCIPAL FINDINGS: To test whether all RET(R114) were originated from a single mutational event, we predicted the approximate age of RET(R114H) by applying a Bayesian method to RET SNPs genotyped in 430 Chinese HSCR patients (of whom 25 individuals had the mutation) to be between 4-23 generations old depending on growth rate. We reasoned that if RET(R114H) was a founder mutation then those with the mutation would share a haplotype on which the mutation resides. Including SNPs spanning 509.31 kb across RET from a recently obtained 500 K genome-wide dataset for a subset of 181 patients (14 RET(R114H) patients), we applied haplotype estimation methods to determine whether there were any segments shared between patients with RET(R114H) that are not present in those without the mutation or controls. Analysis yielded a 250.2 kb (51 SNP) shared segment over the RET gene (and downstream) in only those patients with the mutation with no similar segments found among other patients. CONCLUSIONS: This suggests that RET(R114H) is a founder mutation for HSCR in the Chinese population.


Subject(s)
Founder Effect , Haplotypes , Hirschsprung Disease/genetics , Mutation , Proto-Oncogene Proteins c-ret/genetics , Case-Control Studies , China , Hirschsprung Disease/ethnology , Humans , Polymorphism, Single Nucleotide
17.
Hum Mol Genet ; 19(14): 2917-25, 2010 Jul 15.
Article in English | MEDLINE | ID: mdl-20460270

ABSTRACT

Biliary atresia (BA) is characterized by the progressive fibrosclerosing obliteration of the extrahepatic biliary system during the first few weeks of life. Despite early diagnosis and prompt surgical intervention, the disease progresses to cirrhosis in many patients. The current theory for the pathogenesis of BA proposes that during the perinatal period, a still unknown exogenous factor meets the innate immune system of a genetically predisposed individual and induces an uncontrollable and potentially self-limiting immune response, which becomes manifest in liver fibrosis and atresia of the extrahepatic bile ducts. Genetic factors that could account for the disease, let alone for its high incidence in Chinese, are to be investigated. To identify BA susceptibility loci, we carried out a genome-wide association study (GWAS) using the Affymetrix 5.0 and 500 K marker sets. We genotyped nearly 500 000 single-nucleotide polymorphisms (SNPs) in 200 Chinese BA patients and 481 ethnically matched control subjects. The 10 most BA-associated SNPs from the GWAS were genotyped in an independent set of 124 BA and 90 control subjects. The strongest overall association was found for rs17095355 on 10q24, downstream XPNPEP1, a gene involved in the metabolism of inflammatory mediators. Allelic chi-square test P-value for the meta-analysis of the GWAS and replication results was 6.94 x 10(-9). The identification of putative BA susceptibility loci not only opens new fields of investigation into the mechanisms underlying BA but may also provide new clues for the development of preventive and curative strategies.


Subject(s)
Biliary Atresia/genetics , Chromosomes, Human, Pair 10 , Genetic Loci , Genetic Predisposition to Disease , Asian People/genetics , Case-Control Studies , Chromosome Mapping , Chromosomes, Human, Pair 10/genetics , Female , Gene Frequency , Genome-Wide Association Study , Humans , Linkage Disequilibrium , Male , Polymorphism, Single Nucleotide
18.
Plast Reconstr Surg ; 117(5): 1553-9, 2006 Apr 15.
Article in English | MEDLINE | ID: mdl-16641724

ABSTRACT

BACKGROUND: Functional free muscle transfer for the surgical correction of long-standing facial paralysis has gained validity over the past three decades. These traditionally multistep reconstructions often achieve clinical success, but at the cost of significant morbidity and lengthy recovery periods. To address this dilemma, the authors propose reconstruction using the rectus abdominis and accompanying intercostal nerve in a one-stage neurovascular free flap reanimation procedure. METHODS: Between 1998 and 2001, five patients with long-standing unilateral facial paralysis at the University of Pittsburgh Facial Nerve Center underwent reanimation using the authors' protocol. Preoperative and postoperative assessments included clinical evaluation using the Facial Grading System and electromyography. The patients were followed for a mean of 16 months. RESULTS: At the final postoperative visit, all five patients demonstrated improved levator electromyographic potential, with a median 67 percent improvement. All five patients further demonstrated an increase in zygomaticus electromyographic potential, with a median 225 percent improvement. All five patients demonstrated increased Facial Grading System score at most recent follow-up. CONCLUSIONS: The one-step reanimation using free rectus abdominis neurovascular free flap demonstrated a consistent positive outcome in electromyographic and clinical assessments. The additional benefits of reduced recovery time and anatomical reliability of the flap render the authors' method preferable to other traditional methods of surgical reanimation of the paralyzed face.


Subject(s)
Facial Paralysis/surgery , Surgical Flaps , Electromyography , Facial Paralysis/physiopathology , Humans , Plastic Surgery Procedures/methods , Rectus Abdominis , Suture Techniques , Zygoma/surgery
20.
J Reconstr Microsurg ; 22(1): 5-14, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16425115

ABSTRACT

Reconstruction of large defects of the pelvis and groin sometimes requires microsurgical flaps when the otherwise rich supply of local options fails to be sufficient in difficult and complicated cases. Recipient vessels for microsurgical flaps to the groin and pelvis are important elements in planning such procedures. Seven groups have reported pelvis and groin microsurgical flap cases, and their recipient vessels have included the superior and inferior gluteal vessels, the femoral vessels, the deep perforators of the femoral system, the inferior epigastric vessels, intra-abdominal vessels, and interpositional vein grafts to distant recipient vessels. This review summarizes their experience and describes the recipient vessel options in the pelvic and groin region.


Subject(s)
Arteries/surgery , Groin/blood supply , Pelvis/blood supply , Surgical Flaps/blood supply , Veins/surgery , Graft Survival , Groin/surgery , Humans , Microsurgery/methods , Pelvis/surgery
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